Compounds as inhibitors of hepatitis C virus NS3 serine protease

ABSTRACT

The present invention discloses novel compounds which have HCV protease inhibitory activity as well as methods for preparing such compounds. In another embodiment, the invention discloses pharmaceutical compositions comprising such compounds as well as methods of using them to treat disorders associated with the HCV protease.

This application is a divisional of U.S. application Ser. No. 11/065,531, filed Feb. 24, 2005 now U.S. Pat. No. 7,186,747, and claims the benefit of U.S. Provisional Application, Ser. No. 60/548,535 filed Feb. 27, 2004.

FIELD OF THE INVENTION

The present invention relates to novel hepatitis C virus (“HCV”) protease inhibitors, pharmaceutical compositions containing one or more such inhibitors, methods of preparing and using such inhibitors to treat hepatitis C and related disorders.

BACKGROUND OF THE INVENTION

Hepatitis C virus (HCV) is a (+)-sense single-stranded RNA virus that has been implicated as the major causative agent in non-A, non-B hepatitis (NANBH), particularly in blood-associated NANBH (BB-NANBH) (see, International Patent Application Publication No. WO 89/04669 and European Patent Application Publication No. EP 381 216). NANBH is to be distinguished from other types of viral-induced liver disease, such as hepatitis A virus (HAV), hepatitis B virus (HBV), delta hepatitis virus (HDV), cytomegalovirus (CMV) and Epstein-Barr virus (EBV), as well as from other forms of liver disease such as alcoholism and primary biliar cirrhosis.

Recently, an HCV protease necessary for polypeptide processing and viral replication has been identified, cloned and expressed. (See, e.g. U.S. Pat. No. 5,712,145). This approximately 3000 amino acid polyprotein contains, from the amino terminus to the carboxy terminus, a nucleocapsid protein (C), envelope proteins (E1 and E2) and several non-structural proteins (NS1, 2, 3, 4a, 5a and 5b). NS3 is an approximately 68 kda protein, encoded by approximately 1893 nucleotides of the HCV genome, and has two distinct domains: (a) a serine protease domain consisting of approximately 200 of the N-terminal amino acids; and (b) an RNA-dependent ATPase domain at the C-terminus of the protein. The NS3 protease is considered a member of the chymotrypsin family because of similarities in protein sequence, overall three-dimensional structure and mechanism of catalysis. Other chymotrypsin-like enzymes are elastase, factor Xa, thrombin, trypsin, plasmin, urokinase, tPA and PSA. The HCV NS3 serine protease is responsible for proteolysis of the polypeptide (polyprotein) at the NS3/NS4a, NS4a/NS4b, NS4b/NS5a and NS5a/NS5b junctions and is thus responsible for generating four viral proteins during viral replication. This has made the HCV NS3 serine protease an attractive target for antiviral chemotherapy. The inventive compounds can inhibit such protease. They also can modulate the processing of hepatitis C virus (HCV) polypeptide.

It has been determined that the NS4a protein, an approximately 6 kda polypeptide, is a co-factor for the serine protease activity of NS3. Autocleavage of the NS3/NS4a junction by the NS3/NS4a serine protease occurs intramolecularly (i.e., cis) while the other cleavage sites are processed intermolecularly (i.e., trans).

Analysis of the natural cleavage sites for HCV protease revealed the presence of cysteine at P1 and serine at P1′ and that these residues are strictly conserved in the NS4a/NS4b, NS4b/NS5a and NS5a/NS5b junctions. The NS3/NS4a junction contains a threonine at P1 and a serine at P1′. The Cys→Thr substitution at NS3/NS4a is postulated to account for the requirement of cis rather than trans processing at this junction. See, e.g., Pizzi et al. (1994) Proc. Natl. Acad. Sci. (USA) 91:888-892, Failla et al. (1996) Folding & Design 1:35-42. The NS3/NS4a cleavage site is also more tolerant of mutagenesis than the other sites. See, e.g., Kollykhalov et al. (1994) J. Virol. 68:7525-7533. It has also been found that acidic residues in the region upstream of the cleavage site are required for efficient cleavage. See, e.g., Komoda et al. (1994) J. Virol. 68:7351-7357.

Inhibitors of HCV protease that have been reported include antioxidants (see, International Patent Application Publication No. WO 98/14181), certain peptides and peptide analogs (see, International Patent Application Publication No. WO 98/17679, Landro et al. (1997) Biochem. 36:9340-9348, Ingallinella et al. (1998) Biochem. 37:8906-8914, Llinàs-Brunet et al. (1998) Bioorg. Med. Chem. Lett. 8:1713-1718), inhibitors based on the 70-amino acid polypeptide eglin c (Martin et al. (1998) Biochem. 37:11459-11468, inhibitors affinity selected from human pancreatic secretory trypsin inhibitor (hPSTI-C3) and minibody repertoires (MBip) (Dimasi et al. (1997) J. Virol. 71:7461-7469), cV_(H)E2 (a “camelized” variable domain antibody fragment) (Martin et al. (1997) Protein Eng. 10:607-614), and α1-antichymotrypsin (ACT) (Elzouki et al.) (1997) J. Hepat. 27:42-28). A ribozyme designed to selectively destroy hepatitis C virus RNA has recently been disclosed (see, BioWorld Today 9(217): 4 (Nov. 10, 1998)).

Reference is also made to the PCT Publications, No. WO 98/17679, published Apr. 30, 1998 (Vertex Pharmaceuticals Incorporated); WO 98/22496, published May 28, 1998 (F. Hoffmann-La Roche AG); and WO 99/07734, published Feb. 18, 1999 (Boehringer Ingelheim Canada Ltd.).

HCV has been implicated in cirrhosis of the liver and in induction of hepatocellular carcinoma. The prognosis for patients suffering from HCV infection is currently poor. HCV infection is more difficult to treat than other forms of hepatitis due to the lack of immunity or remission associated with HCV infection. Current data indicates a less than 50% survival rate at four years post cirrhosis diagnosis. Patients diagnosed with localized resectable hepatocellular carcinoma have a five-year survival rate of 10-30%, whereas those with localized unresectable hepatocellular carcinoma have a five-year survival rate of less than 1%.

Reference is made to WO 00/59929 (U.S. Pat. No. 6,608,027, Assignee: Boehringer Ingelheim (Canada) Ltd.; Published Oct. 12, 2000) which discloses peptide derivatives of the formula:

Reference is made to A. Marchetti et al, Synlett, S1, 1000-1002 (1999) describing the synthesis of bicylic analogs of an inhibitor of HCV NS3 protease. A compound disclosed therein has the formula:

Reference is also made to W. Han et al, Bioorganic & Medicinal Chem. Lett, (2000) 10, 711-713, which describes the preparation of certain α-ketoamides, α-ketoesters and α-diketones containing allyl and ethyl functionalities.

Reference is also made to WO 00/09558 (Assignee: Boehringer Ingelheim Limited; Published Feb. 24, 2000) which discloses peptide derivatives of the formula:

where the various elements are defined therein. An illustrative compound of that series is:

Reference is also made to WO 00/09543 (Assignee: Boehringer Ingelheim Limited; Published Feb. 24, 2000) which discloses peptide derivatives of the formula:

where the various elements are defined therein. An illustrative compound of that series is:

Reference is also made to U.S. Pat. No. 6,608,027 (Boehringer Ingelheim, Canada) which discloses NS3 protease inhibitors of the type:

wherein the various moieties are defined therein.

Current therapies for hepatitis C include interferon-α (INF_(α)) and combination therapy with ribavirin and interferon. See, e.g., Beremguer et al. (1998) Proc. Assoc. Am. Physicians 110(2):98-112. These therapies suffer from a low sustained response rate and frequent side effects. See, e.g., Hoofnagle et al. (1997) N. Engl. J. Med. 336:347. Currently, no vaccine is available for HCV infection.

Reference is further made to WO 01/74768 (Assignee: Vertex Pharmaceuticals Inc) published Oct. 11, 2001, which discloses certain compounds of the following general formula (R is defined therein) as NS3-serine protease inhibitors of Hepatitis C virus:

A specific compound disclosed in the afore-mentioned WO 01/74768 has the following formula:

PCT Publications WO 01/77113; WO 01/081325; WO 02/08198; WO 02/08256; WO 02/08187; WO 02/08244; WO 02/48172; WO 02/08251; and pending U.S. patent application, Ser. No. 10/052,386, filed Jan. 18, 2002, disclose various types of peptides and/or other compounds as NS-3 serine protease inhibitors of hepatitis C virus. The disclosures of those applications are incorporated herein by reference thereto.

There is a need for new treatments and therapies for HCV infection. There is a need for compounds useful in the treatment or prevention or amelioration of one or more symptoms of hepatitis C.

There is a need for methods of treatment or prevention or amelioration of one or more symptoms of hepatitis C.

There is a need for methods for modulating the activity of serine proteases, particularly the HCV NS3/NS4a serine protease, using the compounds provided herein.

There is a need for methods of modulating the processing of the HCV polypeptide using the compounds provided herein.

SUMMARY OF THE INVENTION

In its many embodiments, the present invention provides a novel class of inhibitors of the HCV protease, pharmaceutical compositions containing one or more of the compounds, methods of preparing pharmaceutical formulations comprising one or more such compounds, and methods of treatment or prevention of HCV or amelioration of one or more of the symptoms of hepatitis C using one or more such compounds or one or more such formulations. Also provided are methods of modulating the interaction of an HCV polypeptide with HCV protease. Among the compounds provided herein, compounds that inhibit HCV NS3/NS4a serine protease activity are preferred. The present invention discloses compounds, or enantiomers, stereoisomers, rotamers, tautomers, diastereomers or racemates of said compounds, or a pharmaceutically acceptable salt, solvate or ester of said compounds, said compounds having the general structure shown in structural Formula 1:

wherein:

R¹ is H, OR⁸, NR⁹R¹⁰, or CHR⁹R¹⁰, wherein R⁸, R⁹ and R¹⁰ can be the same or different, each being independently selected from the group consisting of H, alkyl-, alkenyl-, alkynyl-, aryl-, heteroalkyl-, heteroaryl-, cycloalkyl-, heterocyclyl-, arylalkyl-, and heteroarylalkyl;

A and M can be the same or different, each being independently selected from R, OR, NHR, NRR′, SR, SO₂R, and halo; or A and M are connected to each other such that the moiety:

shown above in Formula I forms either a three, four, six, seven or eight-membered cycloalkyl, a four to eight-membered heterocyclyl, a six to ten-membered aryl, or a five to ten-membered heteroaryl;

E is C(H) or C(R);

L is C(H), C(R), CH₂C(R), or C(R)CH₂;

R, R′, R², and R³ can be the same or different, each being independently selected from the group consisting of H, alkyl-, alkenyl-, alkynyl-, cycloalkyl-, heteroalkyl-, heterocyclyl-, aryl-, heteroaryl-, (cycloalkyl)alkyl-, (heterocyclyl)alkyl-, aryl-alkyl-, and heteroaryl-alkyl-; or alternately R and R′ in NRR′ are connected to each other such that NRR′ forms a four to eight-membered heterocyclyl;

and Y is selected from the following moieties:

wherein G is NH or O; and R¹⁵, R¹⁶, R¹⁷, R¹⁸, and R¹⁹ can be the same or different, each being independently selected from the group consisting of H, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, cycloalkyl, heterocyclyl, aryl, arylalkyl, heteroaryl, and heteroarylalkyl, or alternately, (i) either R¹⁵ and R¹⁶ are connected to each other to form a four to eight-membered cyclic structure, or R¹⁵ and R¹⁹ are connected to each other to form a four to eight-membered cyclic structure, and (ii) likewise, independently, R¹⁷ and R¹⁸ are connected to each other to form a three to eight-membered cycloalkyl or heterocyclyl;

wherein each of said alkyl, aryl, heteroaryl, cycloalkyl or heterocyclyl can be unsubstituted or optionally independently substituted with one or more moieties selected from the group consisting of: hydroxy, alkoxy, aryloxy, thio, alkylthio, arylthio, amino, amido, alkylamino, arylamino, alkylsulfonyl, arylsulfonyl, sulfonamido, alkylsulfonamido, arylsulfonamido, alkyl, aryl, heteroaryl, keto, carboxy, carbalkoxy, carboxamido, alkoxycarbonylamino, alkoxycarbonyloxy, alkylureido, arylureido, halo, cyano, and nitro.

The above-noted statement “A and M are connected to each other such that the moiety:

shown above in Formula I forms either a three, four, six, seven or eight-membered cycloalkyl, a four to eight-membered heterocyclyl, a six to ten-membered aryl, or a five to ten-membered heteroaryl” can be illustrated in a non-limiting matter as follows. Thus, for example, in the case where A and M are connected such that the moiety:

shown above in Formula I forms a six-membered cycloalkyl(cyclohexyl), Formula I can be depicted as:

One with ordinary skill in the art will appreciate that similar depictions for Formula I can be arrived at when A and M shown above in the moiety:

are connected to form a three, four, seven or eight-membered cycloalkyl, a four to eight-membered heterocyclyl, a six to ten-membered aryl, or a five to ten-membered heteroaryl.

The statement above: “alternately, (i) either R¹⁵ and R¹⁶ are connected to each other to form a four to eight-membered cyclic structure, or R¹⁵ and R¹⁹ are connected to each other to form a four to eight-membered cyclic structure, and (ii) likewise, independently, R¹⁷ and R¹⁸ are connected to each other to form a three to eight-membered cycloalkyl or heterocyclyl” means the following possibilities: (i) that R¹⁵ and R¹⁶ are connected to form a cyclic structure while R¹⁵ and R¹⁹ are not; (ii) that R¹⁵ and R¹⁹ are connected to form a cyclic structure while R¹⁵ and R¹⁶ are not; and that (iii) R¹⁷ and R¹⁸ are independently connected to form a cyclic structure, irrespective of whether the possibilities in (i) and (ii) exist or not.

In the above-noted definitions of R, R′, R², and R³ preferred alkyl is made of one to ten carbon atoms, preferred alkenyl or alkynyl is made of two to ten carbon atoms, preferred cycloalkyl is made of three to eight carbon atoms, and preferred heteroalkyl, heteroaryl or heterocycloalkyl has one to six oxygen, nitrogen, sulfur, or phosphorus atoms.

The compounds represented by Formula I, by themselves or in combination with one or more other suitable agents disclosed herein, can be useful for treating diseases such as, for example, HCV, HIV, AIDS (Acquired Immune Deficiency Syndrome), and related disorders, as well as for modulating the activity of hepatitis C virus (HCV) protease, preventing HCV, or ameliorating one or more symptoms of hepatitis C. Such modulation, treatment, prevention or amelioration can be done with the inventive compounds as well as with pharmaceutical compositions or formulations comprising such compounds. Without being limited to theory, it is believed that the HCV protease may be the NS3 or NS4a protease. The inventive compounds can inhibit such protease. They can also modulate the processing of hepatitis C virus (HCV) polypeptide.

DETAILED DESCRIPTION

In an embodiment, the present invention discloses compounds which are represented by structural Formula 1 or a pharmaceutically acceptable salt, solvate or ester thereof, wherein the various moieties are as defined above.

In another embodiment, R¹ is NR⁹R¹⁰, and R⁹ is H, R¹⁰ is H, or R¹⁴ wherein R¹⁴ is H, alkyl, aryl, heteroalkyl, heteroaryl, cycloalkyl, alkyl-aryl, alkyl-heteroaryl, aryl-alkyl, alkenyl, alkynyl or heteroaryl-alkyl.

In another embodiment, R¹⁴ is selected from the group consisting of:

In another embodiment, R² is selected from the group consisting of the following moieties:

In another embodiment, R³ is selected from the group consisting of:

wherein R³¹ is OH or O-alkyl; and

-   -   R³² is H, C(O)CH₃, C(O)OtBu or C(O)N(H)tBu.

In an additional embodiment, R³ is selected from the group consisting of the following moieties:

In another embodiment, Y is selected from the following moieties:

wherein R¹⁵, R¹⁶, R¹⁷, R¹⁸, and R¹⁹ can be the same or different, each being independently selected from the group consisting of H, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, cycloalkyl, heterocyclyl, aryl, and heteroaryl, or alternately, (i) either R¹⁵ and R¹⁶ are connected to form a four to eight-membered cyclic structure, or R¹⁵ and R¹⁹ are connected to form a four to eight-membered cyclic structure, and (ii) likewise, independently, R¹⁷ and R¹⁸ are connected to form a three to eight-membered cycloalkyl or heterocyclyl;

wherein each of said alkyl, aryl, heteroaryl, cycloalkyl or heterocyclyl can be unsubstituted or optionally independently substituted with one or more moieties selected from the group consisting of: hydroxy, alkoxy, aryloxy, thio, alkylthio, arylthio, amino, amido, alkylamino, arylamino, alkylsulfonyl, arylsulfonyl, sulfonamido, alkylsulfonamido, arylsulfonamido, keto, carboxy, carbalkoxy, carboxamido, alkoxycarbonylamino, alkoxycarbonyloxy, alkylureido, arylureido, halo, cyano, and nitro.

In an additional embodiment, the moiety:

is selected from the group consisting of:

wherein Y³² is selected from the group consisting of:

R¹⁶ is selected from H, methyl, phenyl, benzyl; and

R¹⁵ and R¹⁹ maybe the same or different, each being independently selected from the following:

or alternately, the moiety:

is selected from the following moieties:

In an additional embodiment, R¹⁶ is H. In another embodiment, the moiety:

is selected from the following structures:

In an additional embodiment, the moiety:

is selected from the following structures:

In a still additional embodiment, the moiety:

is selected from the following structures:

In a further additional embodiment, R¹ is NHR¹⁴, where R¹⁴ is selected from the group consisting of:

R² is selected from the group consisting of the following moieties:

R³ is selected from the group consisting of the following moieties:

Y is selected from the group consisting of:

wherein G=NH, and the moiety,

is selected from the group consisting of:

-   -   R¹⁶=H, and     -   R¹⁵ and R¹⁹ can be the same or different, each being         independently selected from the following:

or alternately, the moiety:

is represented by one of the following moieties,

and the moiety:

Yet another embodiment of the invention discloses compounds shown in Table 1, Table 1A, Table 2 and Table 3 later in this Description. Also shown in the Tables are the biological activities of several inventive compounds (as Ki* values).

In an additional embodiment, this invention discloses the following compounds in Table 4:

TABLE 4

In an additional embodiment, the present invention discloses the following compounds in Table 5:

TABLE 5

As used above, and throughout this disclosure, the following terms, unless otherwise indicated, shall be understood to have the following meanings:

“Patient” includes both human and animals.

“Mammal” means humans and other mammalian animals.

“Alkyl” means an aliphatic hydrocarbon group which may be straight or branched and comprising about 1 to about 20 carbon atoms in the chain. Preferred alkyl groups contain about 1 to about 12 carbon atoms in the chain. More preferred alkyl groups contain about 1 to about 6 carbon atoms in the chain. Branched means that one or more lower alkyl groups such as methyl, ethyl or propyl, are attached to a linear alkyl chain. “Lower alkyl” means a group having about 1 to about 6 carbon atoms in the chain which may be straight or branched. The term “substituted alkyl” means that the alkyl group may be substituted by one or more substituents which may be the same or different, each substituent being independently selected from the group consisting of halo, alkyl, aryl, cycloalkyl, cyano, hydroxy, alkoxy, alkylthio, amino, —NH(alkyl),

—NH(cycloalkyl), —N(alkyl)₂, —N(alkyl)₂, carboxy and —C(O)O-alkyl. Non-limiting examples of suitable alkyl groups include methyl, ethyl, n-propyl, isopropyl and t-butyl.

“Alkenyl” means an aliphatic hydrocarbon group containing at least one carbon-carbon double bond and which may be straight or branched and comprising about 2 to about 15 carbon atoms in the chain. Preferred alkenyl groups have about 2 to about 12 carbon atoms in the chain; and more preferably about 2 to about 6 carbon atoms in the chain. Branched means that one or more lower alkyl groups such as methyl, ethyl or propyl, are attached to a linear alkenyl chain. “Lower alkenyl” means about 2 to about 6 carbon atoms in the chain which may be straight or branched. The term “substituted alkenyl” means that the alkenyl group may be substituted by one or more substituents which may be the same or different, each substituent being independently selected from the group consisting of halo, alkyl. aryl, cycloalkyl, cyano, alkoxy and —S(alkyl). Non-limiting examples of suitable alkenyl groups include ethenyl, propenyl, n-butenyl, 3-methylbut-2-enyl, n-pentenyl, octenyl and decenyl.

“Alkynyl” means an aliphatic hydrocarbon group containing at least one carbon-carbon triple bond and which may be straight or branched and comprising about 2 to about 15 carbon atoms in the chain. Preferred alkynyl groups have about 2 to about 12 carbon atoms in the chain; and more preferably about 2 to about 4 carbon atoms in the chain. Branched means that one or more lower alkyl groups such as methyl, ethyl or propyl, are attached to a linear alkynyl chain. “Lower alkynyl” means about 2 to about 6 carbon atoms in the chain which may be straight or branched. Non-limiting examples of suitable alkynyl groups include ethynyl, propynyl, 2-butynyl and 3-methylbutynyl. The term “substituted alkynyl” means that the alkynyl group may be substituted by one or more substituents which may be the same or different, each substituent being independently selected from the group consisting of alkyl, aryl and cycloalkyl.

“Aryl” means an aromatic monocyclic or multicyclic ring system comprising about 6 to about 14 carbon atoms, preferably about 6 to about 10 carbon atoms. The aryl group can be optionally substituted with one or more “ring system substituents” which may be the same or different, and are as defined herein. Non-limiting examples of suitable aryl groups include phenyl and naphthyl.

“Heteroaryl” means an aromatic monocyclic or multicyclic ring system comprising about 5 to about 14 ring atoms, preferably about 5 to about 10 ring atoms, in which one or more of the ring atoms is an element other than carbon, for example nitrogen, oxygen or sulfur, alone or in combination. Preferred heteroaryls contain about 5 to about 6 ring atoms. The “heteroaryl” can be optionally substituted by one or more “ring system substituents” which may be the same or different, and are as defined herein. The prefix aza, oxa or thia before the heteroaryl root name means that at least a nitrogen, oxygen or sulfur atom respectively, is present as a ring atom. A nitrogen atom of a heteroaryl can be optionally oxidized to the corresponding N-oxide. Non-limiting examples of suitable heteroaryls include pyridyl, pyrazinyl, furanyl, thienyl, pyrimidinyl, pyridone (including N-substituted pyridones), isoxazolyl, isothiazolyl, oxazolyl, thiazolyl, pyrazolyl, furazanyl, pyrrolyl, pyrazolyl, triazolyl, 1,2,4-thiadiazolyl, pyrazinyl, pyridazinyl, quinoxalinyl, phthalazinyl, oxindolyl, imidazo[1,2-a]pyridinyl, imidazo[2,1-b]thiazolyl, benzofurazanyl, indolyl, azaindolyl, benzimidazolyl, benzothienyl, quinolinyl, imidazolyl, thienopyridyl, quinazolinyl, thienopyrimidyl, pyrrolopyridyl, imidazopyridyl, isoquinolinyl, benzoazaindolyl, 1,2,4-triazinyl, benzothiazolyl and the like. The term “heteroaryl” also refers to partially saturated heteroaryl moieties such as, for example, tetrahydroisoquinolyl, tetrahydroquinolyl and the like.

“Aralkyl” or “arylalkyl” means an aryl-alkyl- group in which the aryl and alkyl are as previously described. Preferred aralkyls comprise a lower alkyl group. Non-limiting examples of suitable aralkyl groups include benzyl, 2-phenethyl and naphthalenylmethyl. The bond to the parent moiety is through the alkyl.

“Alkylaryl” means an alkyl-aryl- group in which the alkyl and aryl are as previously described. Preferred alkylaryls comprise a lower alkyl group. Non-limiting example of a suitable alkylaryl group is tolyl. The bond to the parent moiety is through the aryl.

“Cycloalkyl” means a non-aromatic mono- or multicyclic ring system comprising about 3 to about 10 carbon atoms, preferably about 5 to about 10 carbon atoms. Preferred cycloalkyl rings contain about 5 to about 7 ring atoms. The cycloalkyl can be optionally substituted with one or more “ring system substituents” which may be the same or different, and are as defined above. Non-limiting examples of suitable monocyclic cycloalkyls include cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl and the like. Non-limiting examples of suitable multicyclic cycloalkyls include 1-decalinyl, norbornyl, adamantyl and the like, as well as partially saturated species such as, for example, indanyl, tetrahydronaphthyl and the like.

“Halogen” or “halo” means fluorine, chlorine, bromine, or iodine. Preferred are fluorine, chlorine and bromine.

“Ring system substituent” means a substituent attached to an aromatic or non-aromatic ring system which, for example, replaces an available hydrogen on the ring system. Ring system substituents may be the same or different, each being independently selected from the group consisting of alkyl, alkenyl, alkynyl, aryl, heteroaryl, aralkyl, alkylaryl, heteroaralkyl, heteroarylalkenyl, heteroarylalkynyl, alkylheteroaryl, hydroxy, hydroxyalkyl, alkoxy, aryloxy, aralkoxy, acyl, aroyl, halo, nitro, cyano, carboxy, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, alkylsulfonyl, arylsulfonyl, heteroarylsulfonyl, alkylthio, arylthio, heteroarylthio, aralkylthio, heteroaralkylthio, cycloalkyl, heterocyclyl, —C(═N—CN)—NH₂, —C(═NH)—NH₂, —C(═NH)—NH(alkyl), Y₁Y₂N—, Y₁Y₂N-alkyl-, Y₁Y₂NC(O)—, Y₁Y₂NSO₂— and —SO₂NY₁Y₂, wherein Y₁ and Y₂ can be the same or different and are independently selected from the group consisting of hydrogen, alkyl, aryl, cycloalkyl, and aralkyl. “Ring system substituent” may also mean a single moiety which simultaneously replaces two available hydrogens on two adjacent carbon atoms (one H on each carbon) on a ring system. Examples of such moiety are methylene dioxy, ethylenedioxy, —C(CH₃)₂— and the like which form moieties such as, for example:

“Heterocyclyl” means a non-aromatic saturated monocyclic or multicyclic ring system comprising about 3 to about 10 ring atoms, preferably about 5 to about 10 ring atoms, in which one or more of the atoms in the ring system is an element other than carbon, for example nitrogen, oxygen or sulfur, alone or in combination. There are no adjacent oxygen and/or sulfur atoms present in the ring system. Preferred heterocyclyls contain about 5 to about 6 ring atoms. The prefix aza, oxa or thia before the heterocyclyl root name means that at least a nitrogen, oxygen or sulfur atom respectively is present as a ring atom. Any —NH in a heterocyclyl ring may exist protected such as, for example, as an —N(Boc), —N(CBz), —N(Tos) group and the like; such protections are also considered part of this invention. The heterocyclyl can be optionally substituted by one or more “ring system substituents” which may be the same or different, and are as defined herein. The nitrogen or sulfur atom of the heterocyclyl can be optionally oxidized to the corresponding N-oxide, S-oxide or S,S-dioxide. Non-limiting examples of suitable monocyclic heterocyclyl rings include piperidyl, pyrrolidinyl, piperazinyl, morpholinyl, thiomorpholinyl, thiazolidinyl, 1,4-dioxanyl, tetrahydrofuranyl, tetrahydrothiophenyl, lactam, lactone, and the like.

It should be noted that in hetero-atom containing ring systems of this invention, there are no hydroxyl groups on carbon atoms adjacent to a N, O or S, as well as there are no N or S groups on carbon adjacent to another heteroatom. Thus, for example, in the ring:

there is no —OH attached directly to carbons marked 2 and 5.

It should also be noted that tautomeric forms such as, for example, the moieties:

are considered equivalent in certain embodiments of this invention.

“Alkynylalkyl” means an alkynyl-alkyl- group in which the alkynyl and alkyl are as previously described. Preferred alkynylalkyls contain a lower alkynyl and a lower alkyl group. The bond to the parent moiety is through the alkyl. Non-limiting examples of suitable alkynylalkyl groups include propargylmethyl.

“Heteroaralkyl” means a heteroaryl-alkyl- group in which the heteroaryl and alkyl are as previously described. Preferred heteroaralkyls contain a lower alkyl group. Non-limiting examples of suitable aralkyl groups include pyridylmethyl, and quinolin-3-ylmethyl. The bond to the parent moiety is through the alkyl.

“Hydroxyalkyl” means a HO-alkyl- group in which alkyl is as previously defined. Preferred hydroxyalkyls contain lower alkyl. Non-limiting examples of suitable hydroxyalkyl groups include hydroxymethyl and 2-hydroxyethyl.

“Acyl” means an H—C(O)—, alkyl-C(O)— or cycloalkyl-C(O)—, group in which the various groups are as previously described. The bond to the parent moiety is through the carbonyl. Preferred acyls contain a lower alkyl. Non-limiting examples of suitable acyl groups include formyl, acetyl and propanoyl.

“Aroyl” means an aryl-C(O)— group in which the aryl group is as previously described. The bond to the parent moiety is through the carbonyl. Non-limiting examples of suitable groups include benzoyl and 1-naphthoyl.

“Alkoxy” means an alkyl-O— group in which the alkyl group is as previously described. Non-limiting examples of suitable alkoxy groups include methoxy, ethoxy, n-propoxy, isopropoxy and n-butoxy. The bond to the parent moiety is through the ether oxygen.

“Aryloxy” means an aryl-O— group in which the aryl group is as previously described. Non-limiting examples of suitable aryloxy groups include phenoxy and naphthoxy. The bond to the parent moiety is through the ether oxygen.

“Aralkyloxy” means an aralkyl-O— group in which the aralkyl group is as previously described. Non-limiting examples of suitable aralkyloxy groups include benzyloxy and 1- or 2-naphthalenemethoxy. The bond to the parent moiety is through the ether oxygen.

“Alkylthio” means an alkyl-S— group in which the alkyl group is as previously described. Non-limiting examples of suitable alkylthio groups include methylthio and ethylthio. The bond to the parent moiety is through the sulfur.

“Arylthio” means an aryl-S— group in which the aryl group is as previously described. Non-limiting examples of suitable arylthio groups include phenylthio and naphthylthio. The bond to the parent moiety is through the sulfur.

“Aralkylthio” means an aralkyl-S— group in which the aralkyl group is as previously described. Non-limiting example of a suitable aralkylthio group is benzylthio. The bond to the parent moiety is through the sulfur.

“Alkoxycarbonyl” means an alkyl-O—CO— group. Non-limiting examples of suitable alkoxycarbonyl groups include methoxycarbonyl and ethoxycarbonyl. The bond to the parent moiety is through the carbonyl.

“Aryloxycarbonyl” means an aryl-O—C(O)— group. Non-limiting examples of suitable aryloxycarbonyl groups include phenoxycarbonyl and naphthoxycarbonyl. The bond to the parent moiety is through the carbonyl.

“Aralkoxycarbonyl” means an aralkyl-O—C(O)— group. Non-limiting example of a suitable aralkoxycarbonyl group is benzyloxycarbonyl. The bond to the parent moiety is through the carbonyl.

“Alkylsulfonyl” means an alkyl-S(O₂)— group. Preferred groups are those in which the alkyl group is lower alkyl. The bond to the parent moiety is through the sulfonyl.

“Arylsulfonyl” means an aryl-S(O₂)— group. The bond to the parent moiety is through the sulfonyl.

The term “substituted” means that one or more hydrogens on the designated atom is replaced with a selection from the indicated group, provided that the designated atom's normal valency under the existing circumstances is not exceeded, and that the substitution results in a stable compound. Combinations of substituents and/or variables are permissible only if such combinations result in stable compounds. By “stable compound” or “stable structure” is meant a compound that is sufficiently robust to survive isolation to a useful degree of purity from a reaction mixture, and formulation into an efficacious therapeutic agent.

The term “one or more” or “at least one”, when indicating the number of substituents, compounds, combination agents and the like, refers to at least one, and up to the maximum number of chemically and physically permissible, substituents, compounds, combination agents and the like, that are present or added, depending on the context. Such techniques and knowledge are well known within the skills of the concerned artisan.

The term “optionally substituted” means optional substitution with the specified groups, radicals or moieties.

The term “isolated” or “in isolated form” for a compound refers to the physical state of said compound after being isolated from a synthetic process or natural source or combination thereof. The term “purified” or “in purified form” for a compound refers to the physical state of said compound after being obtained from a purification process or processes described herein or well known to the skilled artisan, in sufficient purity to be characterizable by standard analytical techniques described herein or well known to the skilled artisan.

It should also be noted that any heteroatom with unsatisfied valences in the text, schemes, examples and Tables herein is assumed to have the hydrogen atom(s) to satisfy the valences.

When a functional group in a compound is termed “protected”, this means that the group is in modified form to preclude undesired side reactions at the protected site when the compound is subjected to a reaction. Suitable protecting groups will be recognized by those with ordinary skill in the art as well as by reference to standard textbooks such as, for example, T. W. Greene et al, Protective Groups in organic Synthesis (1991), Wiley, N.Y.

When any variable (e.g., aryl, heterocycle, R², etc.) occurs more than one time in any constituent or in Formula 1, its definition on each occurrence is independent of its definition at every other occurrence.

As used herein, the term “composition” is intended to encompass a product comprising the specified ingredients in the specified amounts, as well as any product which results, directly or indirectly, from combination of the specified ingredients in the specified amounts.

Prodrugs and solvates of the compounds of the invention are also contemplated herein. The term “prodrug”, as employed herein, denotes a compound that is a drug precursor which, upon administration to a subject, undergoes chemical conversion by metabolic or chemical processes to yield a compound of Formula 1 or a salt and/or solvate thereof. A discussion of prodrugs is provided in T. Higuchi and V. Stella, Pro-drugs as Novel Delivery Systems (1987) 14 of the A.C.S. Symposium Series, and in Bioreversible Carriers in Drug Design, (1987) Edward B. Roche, ed., American Pharmaceutical Association and Pergamon Press, both of which are incorporated herein by reference thereto.

“Solvate” means a physical association of a compound of this invention with one or more solvent molecules. This physical association involves varying degrees of ionic and covalent bonding, including hydrogen bonding. In certain instances the solvate will be capable of isolation, for example when one or more solvent molecules are incorporated in the crystal lattice of the crystalline solid. “Solvate” encompasses both solution-phase and isolatable solvates. Non-limiting examples of suitable solvates include ethanolates, methanolates, and the like. “Hydrate” is a solvate wherein the solvent molecule is H₂O.

“Effective amount” or “therapeutically effective amount” is meant to describe an amount of compound or a composition of the present invention effective in inhibiting the CDK(s) and thus producing the desired therapeutic, ameliorative, inhibitory or preventative effect.

The compounds of Formula 1 can form salts which are also within the scope of this invention. Reference to a compound of Formula 1 herein is understood to include reference to salts thereof, unless otherwise indicated. The term “salt(s)”, as employed herein, denotes acidic salts formed with inorganic and/or organic acids, as well as basic salts formed with inorganic and/or organic bases. In addition, when a compound of Formula 1 contains both a basic moiety, such as, but not limited to a pyridine or imidazole, and an acidic moiety, such as, but not limited to a carboxylic acid, zwitterions (“inner salts”) may be formed and are included within the term “salt(s)” as used herein. Pharmaceutically acceptable (i.e., non-toxic, physiologically acceptable) salts are preferred, although other salts are also useful. Salts of the compounds of the Formula 1 may be formed, for example, by reacting a compound of Formula 1 with an amount of acid or base, such as an equivalent amount, in a medium such as one in which the salt precipitates or in an aqueous medium followed by lyophilization.

Exemplary acid addition salts include acetates, ascorbates, benzoates, benzenesulfonates, bisulfates, borates, butyrates, citrates, camphorates, camphorsulfonates, fumarates, hydrochlorides, hydrobromides, hydroiodides, lactates, maleates, methanesulfonates, naphthalenesulfonates, nitrates, oxalates, phosphates, propionates, salicylates, succinates, sulfates, tartarates, thiocyanates, toluenesulfonates (also known as tosylates,) and the like. Additionally, acids which are generally considered suitable for the formation of pharmaceutically useful salts from basic pharmaceutical compounds are discussed, for example, by P. Stahl et al, Camille G. (eds.) Handbook of Pharmaceutical Salts. Properties, Selection and Use. (2002) Zurich: Wiley-VCH; S. Berge et al, Journal of Pharmaceutical Sciences (1977) 66(1) 1-19; P. Gould, International J. of Pharmaceutics (1986) 33 201-217; Anderson et al, The Practice of Medicinal Chemistry (1996), Academic Press, New York; and in The Orange Book (Food & Drug Administration, Washington, D.C. on their website). These disclosures are incorporated herein by reference thereto.

Exemplary basic salts include ammonium salts, alkali metal salts such as sodium, lithium, and potassium salts, alkaline earth metal salts such as calcium and magnesium salts, salts with organic bases (for example, organic amines) such as dicyclohexylamines, t-butyl amines, and salts with amino acids such as arginine, lysine and the like. Basic nitrogen-containing groups may be quarternized with agents such as lower alkyl halides (e.g. methyl, ethyl, and butyl chlorides, bromides and iodides), dialkyl sulfates (e.g. dimethyl, diethyl, and dibutyl sulfates), long chain halides (e.g. decyl, lauryl, and stearyl chlorides, bromides and iodides), aralkyl halides (e.g. benzyl and phenethyl bromides), and others.

All such acid salts and base salts are intended to be pharmaceutically acceptable salts within the scope of the invention and all acid and base salts are considered equivalent to the free forms of the corresponding compounds for purposes of the invention.

Pharmaceutically acceptable esters of the present compounds include the following groups: (1) carboxylic acid esters obtained by esterification of the hydroxy groups, in which the non-carbonyl moiety of the carboxylic acid portion of the ester grouping is selected from straight or branched chain alkyl (for example, acetyl, n-propyl, t-butyl, or n-butyl), alkoxyalkyl (for example, methoxymethyl), aralkyl (for example, benzyl), aryloxyalkyl (for example, phenoxymethyl), aryl (for example, phenyl optionally substituted with, for example, halogen, C₁₋₄alkyl, or C₁₋₄alkoxy or amino); (2) sulfonate esters, such as alkyl- or aralkylsulfonyl (for example, methanesulfonyl); (3) amino acid esters (for example, L-valyl or L-isoleucyl); (4) phosphonate esters and (5) mono-, di- or triphosphate esters. The phosphate esters may be further esterified by, for example, a C₁₋₂₀ alcohol or reactive derivative thereof, or by a 2,3-di(C₆₋₂₄)acyl glycerol.

Compounds of Formula 1, and salts, solvates, esters and prodrugs thereof, may exist in their tautomeric form (for example, as an amide or imino ether). All such tautomeric forms are contemplated herein as part of the present invention.

All stereoisomers (for example, geometric isomers, optical isomers, and the like) of the present compounds (including those of the salts, solvates and prodrugs of the compounds as well as the salts and solvates of the prodrugs), such as those which may exist due to asymmetric carbons on various substituents, including enantiomeric forms (which may exist even in the absence of asymmetric carbons), rotameric forms, atropisomers, and diastereomeric forms, are contemplated within the scope of this invention, as are positional isomers (such as, for example, 4-pyridyl and 3-pyridyl). Individual stereoisomers of the compounds of the invention may, for example, be substantially free of other isomers, or may be admixed, for example, as racemates or with all other, or other selected, stereoisomers. The chiral centers of the present invention can have the S or R configuration as defined by the IUPAC 1974 Recommendations. The use of the terms “salt”, “solvate” “prodrug” and the like, is intended to equally apply to the salt, solvate and prodrug of enantiomers, stereoisomers, rotamers, tautomers, positional isomers, racemates or prodrugs of the inventive compounds.

Polymorphic forms of the compounds of Formula I, and of the salts, solvates, esters and prodrugs of the compounds of Formula I, are intended to be included in the present invention.

It is to be understood that the utility of the compounds of Formula 1 for the therapeutic applications discussed herein is applicable to each compound by itself or to the combination or combinations of one or more compounds of Formula 1 as illustrated, for example, in the next immediate paragraph. The same understanding also applies to pharmaceutical composition(s) comprising such compound or compounds and method(s) of treatment involving such compound or compounds.

The compounds according to the invention can have pharmacological properties; in particular, the compounds of Formula 1 can be inhibitors of HCV protease, each compound by itself or one or more compounds of Formula 1 can be combined with one or more compounds selected from within Formula 1. The compound(s) can be useful for treating diseases such as, for example, HCV, HIV, (AIDS, Acquired Immune Deficiency Syndrome), and related disorders, as well as for modulating the activity of hepatitis C virus (HCV) protease, preventing HCV, or ameliorating one or more symptoms of hepatitis C.

The compounds of Formula 1 may be used for the manufacture of a medicament to treat disorders associated with the HCV protease, for example, the method comprising bringing into intimate contact a compound of Formula 1 and a pharmaceutically acceptable carrier.

In another embodiment, this invention provides pharmaceutical compositions comprising the inventive compound or compounds as an active ingredient. The pharmaceutical compositions generally additionally comprise at least one pharmaceutically acceptable carrier diluent, excipient or carrier (collectively referred to herein as carrier materials). Because of their HCV inhibitory activity, such pharmaceutical compositions possess utility in treating hepatitis C and related disorders.

In yet another embodiment, the present invention discloses methods for preparing pharmaceutical compositions comprising the inventive compounds as an active ingredient. In the pharmaceutical compositions and methods of the present invention, the active ingredients will typically be administered in admixture with suitable carrier materials suitably selected with respect to the intended form of administration, i.e. oral tablets, capsules (either solid-filled, semi-solid filled or liquid filled), powders for constitution, oral gels, elixirs, dispersible granules, syrups, suspensions, and the like, and consistent with conventional pharmaceutical practices. For example, for oral administration in the form of tablets or capsules, the active drug component may be combined with any oral non-toxic pharmaceutically acceptable inert carrier, such as lactose, starch, sucrose, cellulose, magnesium stearate, dicalcium phosphate, calcium sulfate, talc, mannitol, ethyl alcohol (liquid forms) and the like. Moreover, when desired or needed, suitable binders, lubricants, disintegrating agents and coloring agents may also be incorporated in the mixture. Powders and tablets may be comprised of from about 5 to about 95 percent inventive composition.

Suitable binders include starch, gelatin, natural sugars, corn sweeteners, natural and synthetic gums such as acacia, sodium alginate, carboxymethylcellulose, polyethylene glycol and waxes. Among the lubricants there may be mentioned for use in these dosage forms, boric acid, sodium benzoate, sodium acetate, sodium chloride, and the like. Disintegrants include starch, methylcellulose, guar gum and the like.

Sweetening and flavoring agents and preservatives may also be included where appropriate. Some of the terms noted above, namely disintegrants, diluents, lubricants, binders and the like, are discussed in more detail below.

Additionally, the compositions of the present invention may be formulated in sustained release form to provide the rate controlled release of any one or more of the components or active ingredients to optimize the therapeutic effects, i.e. HCV inhibitory activity and the like. Suitable dosage forms for sustained release include layered tablets containing layers of varying disintegration rates or controlled release polymeric matrices impregnated with the active components and shaped in tablet form or capsules containing such impregnated or encapsulated porous polymeric matrices.

Liquid form preparations include solutions, suspensions and emulsions. As an example may be mentioned water or water-propylene glycol solutions for parenteral injections or addition of sweeteners and pacifiers for oral solutions, suspensions and emulsions. Liquid form preparations may also include solutions for intranasal administration.

Aerosol preparations suitable for inhalation may include solutions and solids in powder form, which may be in combination with a pharmaceutically acceptable carrier such as inert compressed gas, e.g. nitrogen.

For preparing suppositories, a low melting wax such as a mixture of fatty acid glycerides such as cocoa buffer is first melted, and the active ingredient is dispersed homogeneously therein by stirring or similar mixing. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool and thereby solidify.

Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for either oral or parenteral administration. Such liquid forms include solutions, suspensions and emulsions.

The compounds of the invention may also be deliverable transdermally. The transdermal compositions may take the form of creams, lotions, aerosols and/or emulsions and can be included in a transdermal patch of the matrix or reservoir type as are conventional in the art for this purpose.

The compounds of the invention may also be administered orally, intravenously, intranasally or subcutaneously.

The compounds of the invention may also comprise preparations which are in a unit dosage form. In such form, the preparation is subdivided into suitably sized unit doses containing appropriate quantities of the active components, e.g., an effective amount to achieve the desired purpose.

The quantity of the inventive active composition in a unit dose of preparation may be generally varied or adjusted from about 1.0 milligram to about 1,000 milligrams, preferably from about 1.0 to about 950 milligrams, more preferably from about 1.0 to about 500 milligrams, and typically from about 1 to about 250 milligrams, according to the particular application. The actual dosage employed may be varied depending upon the patient's age, sex, weight and severity of the condition being treated. Such techniques are well known to those skilled in the art.

Generally, the human oral dosage form containing the active ingredients can be administered 1 or 2 times per day. The amount and frequency of the administration will be regulated according to the judgment of the attending clinician. A generally recommended daily dosage regimen for oral administration may range from about 1.0 milligram to about 1,000 milligrams per day, in single or divided doses.

Some useful terms are described below:

Capsule—refers to a special container or enclosure made of methyl cellulose, polyvinyl alcohols, or denatured gelatins or starch for holding or containing compositions comprising the active ingredients. Hard shell capsules are typically made of blends of relatively high gel strength bone and pork skin gelatins. The capsule itself may contain small amounts of dyes, opaquing agents, plasticizers and preservatives.

Tablet—refers to a compressed or molded solid dosage form containing the active ingredients with suitable diluents. The tablet can be prepared by compression of mixtures or granulations obtained by wet granulation, dry granulation or by compaction.

Oral gel—refers to the active ingredients dispersed or solubilized in a hydrophillic semi-solid matrix.

Powder for constitution refers to powder blends containing the active ingredients and suitable diluents which can be suspended in water or juices.

Diluent—refers to substances that usually make up the major portion of the composition or dosage form. Suitable diluents include sugars such as lactose, sucrose, mannitol and sorbitol; starches derived from wheat, corn, rice and potato; and celluloses such as microcrystalline cellulose. The amount of diluent in the composition can range from about 10 to about 90% by weight of the total composition, preferably from about 25 to about 75%, more preferably from about 30 to about 60% by weight, even more preferably from about 12 to about 60%.

Disintegrant—refers to materials added to the composition to help it break apart (disintegrate) and release the medicaments. Suitable disintegrants include starches; “cold water soluble” modified starches such as sodium carboxymethyl starch; natural and synthetic gums such as locust bean, karaya, guar, tragacanth and agar; cellulose derivatives such as methylcellulose and sodium carboxymethylcellulose; microcrystalline celluloses and cross-linked microcrystalline celluloses such as sodium croscarmellose; alginates such as alginic acid and sodium alginate; clays such as bentonites; and effervescent mixtures. The amount of disintegrant in the composition can range from about 2 to about 15% by weight of the composition, more preferably from about 4 to about 10% by weight.

Binder—refers to substances that bind or “glue” powders together and make them cohesive by forming granules, thus serving as the “adhesive” in the formulation. Binders add cohesive strength already available in the diluent or bulking agent. Suitable binders include sugars such as sucrose; starches derived from wheat, corn rice and potato; natural gums such as acacia, gelatin and tragacanth; derivatives of seaweed such as alginic acid, sodium alginate and ammonium calcium alginate; cellulosic materials such as methylcellulose and sodium carboxymethylcellulose and hydroxypropylmethylcellulose; polyvinylpyrrolidone; and inorganics such as magnesium aluminum silicate. The amount of binder in the composition can range from about 2 to about 20% by weight of the composition, more preferably from about 3 to about 10% by weight, even more preferably from about 3 to about 6% by weight.

Lubricant—refers to a substance added to the dosage form to enable the tablet, granules, etc. after it has been compressed, to release from the mold or die by reducing friction or wear. Suitable lubricants include metallic stearates such as magnesium stearate, calcium stearate or potassium stearate; stearic acid; high melting point waxes; and water soluble lubricants such as sodium chloride, sodium benzoate, sodium acetate, sodium oleate, polyethylene glycols and d'l-leucine. Lubricants are usually added at the very last step before compression, since they must be present on the surfaces of the granules and in between them and the parts of the tablet press. The amount of lubricant in the composition can range from about 0.2 to about 5% by weight of the composition, preferably from about 0.5 to about 2%, more preferably from about 0.3 to about 1.5% by weight.

Glident—material that prevents caking and improve the flow characteristics of granulations, so that flow is smooth and uniform. Suitable glidents include silicon dioxide and talc. The amount of glident in the composition can range from about 0.1% to about 5% by weight of the total composition, preferably from about 0.5 to about 2% by weight.

Coloring agents—excipients that provide coloration to the composition or the dosage form. Such excipients can include food grade dyes and food grade dyes adsorbed onto a suitable adsorbent such as clay or aluminum oxide. The amount of the coloring agent can vary from about 0.1 to about 5% by weight of the composition, preferably from about 0.1 to about 1%.

Bioavailability—refers to the rate and extent to which the active drug ingredient or therapeutic moiety is absorbed into the systemic circulation from an administered dosage form as compared to a standard or control.

Conventional methods for preparing tablets are known. Such methods include dry methods such as direct compression and compression of granulation produced by compaction, or wet methods or other special procedures. Conventional methods for making other forms for administration such as, for example, capsules, suppositories and the like are also well known.

Another embodiment of the invention discloses the use of the inventive compounds or pharmaceutical compositions disclosed above for treatment of diseases such as, for example, hepatitis C and the like. The method comprises administering a therapeutically effective amount of the inventive compound or pharmaceutical composition to a patient having such a disease or diseases and in need of such a treatment.

In yet another embodiment, the compounds of the invention may be used for the treatment of HCV in humans in monotherapy mode or in a combination therapy (e.g., dual combination, triple combination etc.) mode such as, for example, in combination with antiviral and/or immunomodulatory agents. Examples of such antiviral and/or immunomodulatory agents include Ribavirin (from Schering-Plough Corporation, Madison, N.J.) and Levovirin™ (from ICN Pharmaceuticals, Costa Mesa, Calif.), VP 50406™ (from Viropharma, Incorporated, Exton, Pa.), ISIS 14803™ (from ISIS Pharmaceuticals, Carlsbad, Calif.), Heptazyme™ (from Ribozyme Pharmaceuticals, Boulder, Colo.), VX 497™ (from Vertex Pharmaceuticals, Cambridge, Mass.), Thymosin™ (from SciClone Pharmaceuticals, San Mateo, Calif.), Maxamine™ (Maxim Pharmaceuticals, San Diego, Calif.), mycophenolate mofetil (from Hoffman-LaRoche, Nutley, N.J.), interferon (such as, for example, interferon-alpha, PEG-interferon alpha conjugates) and the like. “PEG-interferon alpha conjugates” are interferon alpha molecules covalently attached to a PEG molecule. Illustrative PEG-interferon alpha conjugates include interferon alpha-2a (Roferon™, from Hoffman La-Roche, Nutley, N.J.) in the form of pegylated interferon alpha-2a (e.g., as sold under the trade name Pegasys™), interferon alpha-2b (Intron™, from Schering-Plough Corporation) in the form of pegylated interferon alpha-2b (e.g., as sold under the trade name PEG-Intron™), interferon alpha-2c (Berofor Alpha™, from Boehringer Ingelheim, Ingelheim, Germany) or consensus interferon as defined by determination of a consensus sequence of naturally occurring interferon alphas (Infergen™, from Amgen, Thousand Oaks, Calif.).

As stated earlier, the invention includes tautomers, rotamers, enantiomers and other stereoisomers of the inventive compounds also. Thus, as one skilled in the art appreciates, some of the inventive compounds may exist in suitable isomeric forms. Such variations are contemplated to be within the scope of the invention.

Another embodiment of the invention discloses a method of making the compounds disclosed herein. The compounds may be prepared by several techniques known in the art. Illustrative procedures are outlined in the following reaction schemes. The illustrations should not be construed to limit the scope of the invention which is defined in the appended claims. Alternative mechanistic pathways and analogous structures will be apparent to those skilled in the art.

It is to be understood that while the following illustrative schemes describe the preparation of a few representative inventive compounds, suitable substitution of any of both the natural and unnatural amino acids will result in the formation of the desired compounds based on such substitution. Such variations are contemplated to be within the scope of the invention.

For the procedures described below, the following abbreviations are used:

ABBREVIATIONS

Abbreviations which are used in the descriptions of the schemes, preparations and the examples that follow are:

-   THF: Tetrahydrofuran -   DMF: N,N-Dimethylformamide -   EtOAc: Ethyl acetate -   AcOH: Acetic acid -   HOOBt: 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one -   EDCI: 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride -   NMM: N-Methylmorpholine -   ADDP: 1,1′-(Azodicarbobyl)dipiperidine -   DEAD: Diethylazodicarboxylate -   MeOH: Methanol -   EtOH: Ethanol -   Et₂O: Diethyl ether -   DMSO: Dimethylsulfoxide -   HOBt: N-Hydroxybenzotriazole -   PyBrOP: Bromo-tris-pyrrolidinophosphonium hexafluorophosphate -   DCM: Dichloromethane -   DCC: 1,3-Dicyclohexylcarbodiimide -   TEMPO: 2,2,6,6-Tetramethyl-1-piperidinyloxy -   Phg: Phenylglycine -   Chg: Cyclohexylglycine -   Bn: Benzyl -   Bzl: Benzyl -   Et: Ethyl -   Ph: Phenyl -   iBoc: isobutoxycarbonyl -   iPr: isopropyl -   ^(t)Bu or Bu^(t): tert-Butyl -   Boc: tert-Butyloxycarbonyl -   Cbz: Benzyloxycarbonyl -   Cp: Cylcopentyldienyl -   Ts: p-toluenesulfonyl -   Me: Methyl -   HATU: O-(7-azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium     hexafluorophosphate -   DMAP: 4-N,N-Dimethylaminopyridine -   BOP: Benzotriazol-1-yl-oxy-tris(dimethylamino)hexafluorophosphate -   PCC: Pyridiniumchlorochromate

General Schemes for Preparation of Target Compounds

Compounds of the present invention were synthesized using the general schemes (Methods A-E) described below.

Method A

Deprotection of the N-Boc functionality of 1.01 under acidic conditions provided the hydrochloride salt 1.02 which was subsequently coupled with N-Boc-tert-leucine under peptide coupling methodology to afford 1.03. N-Boc deprotection followed by treatment with appropriate isocyanate gave the urea 1.05. Hydrolysis of the methyl ester provided the acid 1.06. Peptide coupling of the acid 1.06 with the appropriate P₁—P′ primary amide moiety afforded the hydroxyl amide 1.07. Oxidation (Moffatt or related process—T. T. Tidwell, Synthesis, 1990, 857; or Dess-Martin's—J. Org. Chem., 1983, 48, 4155) resulted in the target compound 1.08.

Method B

Peptide coupling of the acid 1.06 with the appropriate P₁—P′ secondary amide moiety afforded the hydroxyl amide 1.09. Oxidation (Moffatt or Dess-Martin's) resulted in the target compound 1.10.

Method C

In another variation, peptide coupling of the N-Boc-P₂—P₃-acid 1.17 with the appropriate P₁—P′ amide moiety afforded the hydroxyl amide 1.11. Oxidation (Moffatt or Dess-Martin's) resulted in the keto amide 1.12. Deprotection of the N-Boc functionality gave the hydrochloride salt 1.13. Treatment with a suitable isocyanate (or isocyanate equivalent) resulted in the target compound 1.14.

Method D

In yet another variation, the hydrochloride salt 1.13 was converted to the 4-nitrophenyl carbamate 1.15 by reaction with 4-nitrophenyl chloroformate. Subsequent treatment with an amine (or amine hydrochloride salt) of choice provided the target compound 1.14.

Method E

In yet another variation, the dipeptide hydrochloride salt 1.03 was converted to the 4-nitrophenyl carbamate as described above. Treatment with an amine (or amine hydrochloride salt) of choice provided the urea derivative 1.05. Hydrolysis and further elaboration as described in Methods A/B provided the target compounds 1.14.

Preparation of Intermediates Preparation of P₁—P′ Moieties Preparation of Intermediates 10.11 and 10.12

Step 1

A stirred solution of ketimine 10.01 (50 g, 187.1 mmol) under N₂ in dry THF (400 mL) was cooled to −78° C. and treated with 1 M solution of K—^(t)BuO (220 mL, 1.15 equiv.) in THF. The reaction mixture was warmed to 0° C. and stirred for 1 h and treated with bromomethyl cyclobutane (28 mL, 249 mmol). The reaction mixture was stirred at room temperature for 48 h and concentrated in vacuo. The residue was dissolved in Et₂O (300 mL) and treated with aq. HCl (2 M, 300 mL) The resulting solution was stirred at room temperature for 5 h and extracted with Et₂O (1 L). The aqueous layer was made basic to pH ˜12-14 with NaOH (50% aq.) and extracted with CH₂Cl₂ (3×300 mL). The combined organic layers were dried (MgSO₄), filtered, and concentrated to give the pure amine (10.02, 18 g) as a colorless oil.

Step 2

A solution of the amine 10.02 (18 g, 105.2 mmol) at 0° C. in CH₂Cl₂ (350 mL) was treated with di-tert-butyldicarbonate (23 g, 105.4 mmol) and stirred at rt. for 12 h. After the completion of the reaction (TLC), the reaction mixture was concentrated in vacuo and the residue was dissolved in THF/H₂O (200 ml, 1:1) and treated with LiOH.H₂O (6.5 g, 158.5 mmol) and stirred at room temperature for 3 h. The reaction mixture was concentrated and the basic aqueous layer was extracted with Et₂O. The aqueous layer was acidified with conc. HCl to pH˜1-2 and extracted with CH₂Cl₂. The combined organic layers were dried (MgSO₄), filtered, and concentrated in vacuo to yield 10.03 as a colorless viscous oil which was used for the next step without any further purification.

Step 3

A solution of the acid 10.03 (15.0 g, 62 mmol) in CH₂Cl₂ (250 mL) was treated with BOP reagent (41.1 g, 93 mmol), N-methyl morpholine (27 mL), N,O-dimethyl hydroxylamine hydrochloride (9.07 g, 93 mmol) and stirred overnight at rt. The reaction mixture was diluted with 1 N aq. HCl (250 mL), and the layers were separated and the aqueous layer was extracted with CH₂Cl₂ (3×300 ml). The combined organic layers were dried (MgSO₄), filtered and concentrated in vacuo and purified by chromatography (SiO₂, EtOAc/Hex 2:3) to yield the amide 10.04 (15.0 g) as a colorless solid.

Step 4

A solution of the amide 10.04 (15 g, 52.1 mmol) in dry THF (200 mL) was treated dropwise with a solution of LiAlH₄ (1M, 93 mL, 93 mmol) at 0° C. The reaction mixture was stirred at room temperature for 1 h and carefully quenched at 0° C. with a solution of KHSO₄ (10% aq.) and stirred for 0.5 h. The reaction mixture was diluted with aq. HCl (1 M, 150 mL) and extracted with CH₂Cl₂ (3×200 mL), The combined organic layers were washed with aq. HCl (1 M), saturated NaHCO₃, brine, and dried (MgSO₄). The mixture was filtered and concentrated in vacuo to yield 10.05 as a viscous colorless oil (14 g).

Step 5

A solution of the aldehyde 10.05 (14 g, 61.6 mmol) in CH₂Cl₂ (50 mL), was treated with Et₃N (10.73 mL, 74.4 mmol), and acetone cyanohydrin (10.86 g, 127.57 mmol) and stirred at room temperature for 24 hrs. The reaction mixture was concentrated in vacuo and diluted with aq. HCl (1 M, 200 mL) and extracted into CH₂Cl₂ (3×200 mL). The combined organic layer were washed with H₂O, brine, dried (MgSO₄), filtered, concentrated in vacuo and purified by chromatography (SiO₂, EtOAc/Hex 1:4) to yield 10.06 (10.3 g) as a colorless liquid

Step 6

Methanol saturated with HCl*, prepared by bubbling HCl gas through CH₃OH (700 ml) at 0° C., was treated with the cyanohydrin 10.06 and heated to reflux for 24 h. The reaction was concentrated in vacuo to yield 10.07, which was used in the next step without purification.

*Alternatively 6M HCl prepared by addition of AcCl to dry methanol can also be used.

Step 7

A solution of the amine hydrochloride 10.07 in CH₂Cl₂ (200 mL) was treated with Et₃N (45.0 mL, 315 mmol) and Boc₂O (45.7 g, 209 mmol) at −78° C. The reaction mixture was then stirred at room temperature overnight and diluted with HCl (2 M, 200 mL) and extracted into CH₂Cl₂. The combined organic layer were dried (MgSO₄) filtered, concentrated in vacuo and purified by chromatography (EtOAc/Hex 1:4) to yield hydroxy ester 10.08.

Step 8

A solution of methyl ester 10.08 (3 g, 10.5 mmol) in THF/H₂O (1:1) was treated with LiOH.H₂O (645 mg, 15.75 mmol) and stirred at rt. for 2 h. The reaction mixture was acidified with aq HCl (1 M, 15 mL) and concentrated in vacuo. The residue was dried in vacuum to afford 10.09 in quantitative yield.

Step 9

A solution of the acid 10.09 (from above) in CH₂Cl₂ (50 mL) and DMF (25 mL) was treated with NH₄Cl (2.94 g, 55.5 mmol), EDCI (3.15 g, 16.5 mmol), HOOBt (2.69 g, 16.5 mmol), and NMM (4.4 g, 44 mmol). The reaction mixture was stirred at room temperature for 3 d. The solvents were removed under vacuo and the residue was diluted with aq. HCl (250 mL) and extracted with CH₂Cl₂. The combined organic layers were washed with aq. Sat'd. NaHCO₃, dried (MgSO₄) filtered concentrated in vacuo to obtain 10.10, which was used as it was in the following steps. (Alternatively 10.10 can also be obtained directly by the reaction of 10.06 (4.5 g, 17.7 mmol) with aq. H₂O₂ (10 mL), LiOH.H₂O (820 mg, 20.8 mmol) at 0° C. in 50 mL of CH₃OH for 0.5 h.)

Step 10

A solution of 10.10 obtained in the previous step was dissolved in 4 N HCl in dioxane and stirred at rt. for 2 h. The reaction mixture was concentrated in vacuo to give the intermediate 10.11 as a solid, which was used without further purification.

Step 11

The required intermediate 10.12 was obtained from compound 10.09 using essentially the procedures described above in Steps 9, 10 with appropriate reagents.

Preparation of Intermediate 11.01

Step 1

To a solution of 4-pentyn-1-ol, 11.02 (4.15 g; Aldrich) was added Dess-Martin Periodinane (30.25 g; Aldrich) and the resulting mixture was stirred for 45 min. before the addition of (tert-Butoxycarbonylmethylene)triphenylphosphorane (26.75 g; Aldrich). The resulting dark reaction was stirred overnight, diluted with EtOAc), washed with aq. sodium sulfite. sat. aq. NaHCO3, water, brine and dried. The volatiles were removed under reduced pressure and the residue was purified by silica gel column chromatography using 1% EtOAc in hexanes as eluent to give the desired compound, 11.03 (3.92 g). Some impure fractions were also obtained but set aside at this time.

Step 2

Using the alkene 11.03 (1.9 g) in n-propanol (20 ml; Aldrich)), benzyl carbamate (4.95 g; Aldrich) in n-propanol (40 ml), NaOH (1.29 g) in water (79 ml), tert-butyl hypochlorite (3.7 ml), (DHQ)2PHAL (0.423 g; Aldrich)) in n-propanol (37.5 ml), and potassium osmate:dehydrate (0.1544 g; Aldrich) and the procedure set forth in Angew. Chem. Int. Ed. Engl (1998), 35, (23/24), pp. 2813-7. gave a crude product which was purified by silica gel column chromatography using EtOAc:Hexanes (1:5) to give the desired amino alcohol 11.04 (1.37 g, 37%) as a white solid.

Step 3

To the ester 11.04 (0.700 g) was added 4M HCl in dioxane (20 ml; Aldrich) and the resulting mixture was allowed to stand at room temperature overnight. The volatiles were removed under reduced pressure to give the acid 11.05 (0.621 g) as a white solid.

Step 4

BOP reagent (3.65 g; Sigma) followed by triethylamine (3.45 ml) were added to a dichloromethane (20 ml) solution of the carboxylic acid 11.05 (2.00 g) and allyl amine (0.616 ml) at room temperature and the resulting mixture was stirred overnight. The reaction mixture was partitioned between EtOAc and 10% aq. HCl. The organic phase was separated, washed with sat. aq. sodium bicarbonate, water, dried (magnesium sulfate). The crude reaction product was purified by silica gel column chromatography using (EtOAc:Hexanes; 70:30) as eluent to provide the desired amide 11.01 (1.73 g) as a viscous yellow oil.

Preparation of Intermediates 12.03 and 12.04

Step 1

Compound 12.01 was converted to the required material 12.02 using essentially the procedures described for Intermediate 10.11, Steps 3-8.

Step 2

Compound 12.02 was converted to the required intermediate 12.03 using essentially the procedures described for Intermediate 10.11, Steps 9, 10.

Step 3

Compound 12.02 was converted to the required intermediate 12.03 using essentially the procedures described for Intermediate 10.12, Step 11.

Preparation of Intermediate 13.01

Step 1

To a stirred solution of 1-nitrobutane, 13.02 (16.5 g, 0.16 mol) and glyoxylic acid in H₂O (28.1 g, 0.305 mol) and MeOH (122 mL) at 0° C.-5° C., was added dropwise triethylamine (93 mL, 0.667 mol) over 2 hrs. The solution was warmed to room temperature, stirred overnight and concentrated to dryness to give an oil. The oil was then dissolved in H₂O and acidified to pH=1 with 10% HCl, followed by extraction with EtOAc. The combined organic solution was washed with brine, dried over Na₂SO₄, filtered and concentrated to dryness to give the product 13.03 (28.1 g, 99% yield).

Step 2

To a stirred solution of compound 13.03 (240 g, 1.35 mol) in acetic acid (1.25 L) was added 10% Pd/C (37 g). The resulting solution was hydrogenated at 59 psi for 3 hrs and then at 60 psi overnight. The acetic acid was then evaporated and azeotroped 3 times with toluene, then triturated with MeOH and ether. The solution was then filtered and azeotroped twice with toluene to afford 13.04 as an off white solid (131 g, 0.891 mol, 66%).

Step 3

To a stirred solution of the amino acid 13.04 (2.0 g, 13.6 mmol) in dioxane (10 mL) and H₂O (5 mL) at 0° C., was added 1N NaOH solution (4.3 mL, 14.0 mmol). The resulting solution was stirred for 10 minutes, followed by addition of di-t-butyldicarbonate (0.110 g, 14.0 mmol) and stirred at 0° C. for 15 minutes. The solution was then warmed to room temperature, stirred for 45 minutes and kept at refrigerator overnight and concentrated to dryness to give a crude material. To the solution of this crude material in EtOAc (100 mL) and ice, was added KHSO₄ (3.36 g) and H₂O (32 mL) and stirred for 4-6 minutes. The organic layer was then separated and the aqueous layer was extracted twice with EtOAc and the combined organic layer was washed with water, brine, dried over Na₂SO₄, filtered and concentrated to dryness to give the product 13.05 as a clear gum (3.0 g, 89% yield).

Step 4

Compound 13.05 was converted to the required intermediate 13.01 using essentially the procedures described for Intermediate 10.12, Step 11.

Preparation of Intermediate 14.01

Step 1

Compound 14.02 was converted to the required material 14.03 using essentially the procedures described for Intermediate 13.01, Steps 1-3.

Step 2

Compound 14.03 was converted to the required intermediate 14.01 using essentially the procedures described for Intermediate 10.12, Step 11.

Preparation of Intermediate 15.01

Step 1

To a suspension of silver nitrite (9 g, 58.5 mmol) in diethyl ether (25 mL) at 0° C. was added a solution of 4-iodo-1,1,1-trifluorobutane, 15.02 (10 g, 42.0 mmol) in diethyl ether (25 mL) slowly through an addition funnel (approx. 15 min). The resulting mixture was vigorously stirred at 0° C. and warmed to rt. After 50 h, the solid material was filtered off through a celite pad. The resulting diethyl ether solution was concentrated in vacuo to give 15.03 as colorless oil, which was used without further purification.

Step 2

Compound 15.03 was converted to the required material 15.04 using essentially the procedures described for Intermediate 13.01, Steps 1-3.

Step 3

Compound 15.04 was converted to the required intermediate 15.01 using essentially the procedures described for Intermediate 10.12, Step 11.

Preparation of Intermediate 16.01

The acid 16.02 (Winkler, D.; Burger, K., Synthesis, 1996, 1419) is processed as described above (preparation of Intermediate 10.12) to give the expected intermediate 16.01.

Preparation of P₂/P₃—P₂ Moieties Preparation of Intermediate 20.01

The amino ester 20.01 was prepared following the method of R. Zhang and J.

S. Madalengoitia (J. Org. Chem. 1999, 64, 330), with the exception that the Boc group was cleaved by the reaction of the Boc-protected amino acid with methanolic HCl (4M HCl in dioxane was also employed for the deprotection). (Note: In a variation of the reported synthesis, the sulfonium ylide was replaced with the corresponding phosphonium ylide)

Preparation of Intermediate 20.04

Step 1

A solution of commercial amino acid Boc-Chg-OH, 20.02 (Senn chemicals, 6.64 g, 24.1 mmol) and amine hydrochloride 20.01 (4.5 g, 22 mmol) in CH₂Cl₂ (100 mL) at 0° C. was treated with BOP reagent and stirred at rt. for 15 h. The reaction mixture was concentrated in vacuo, then it was diluted with aq. 1 M HCl and extracted into EtOAc (3×200 mL). The combined organic layers were washed with sat'd. NaHCO₃ (200 mL), dried (MgSO₄), filtered and concentrated in vacuo, and chromatographed (SiO₂, EtOAc/Hex 3:7) to obtain 20.03 (6.0 g) as a colorless solid.

Step 2

A solution of methyl ester 20.03 (4.0 g, 9.79 mmol) in THF/H₂O (1:1) was treated with LiOH.H₂O (401 mg, 9.79 mmol) and stirred at rt. for 3 h. The reaction mixture was acidified with aq. HCl and concentrated in vacuo to obtain the required intermediate, free acid 20.04.

Preparation of Intermediate 20.08

Step 1

A solution of Boc-tert-Leu 20.05 (Fluka, 5.0 g 21.6 mmol) in dry CH₂Cl₂/DMF (50 mL, 1:1) was cooled to 0° C. and treated with the amine salt 20.01 (5.3 g, 25.7 mmol), NMM (6.5 g, 64.8 mmol) and BOP reagent (11.6 g, 25.7 mmol). The reaction was stirred at rt. for 24 h, diluted with aq. HCl (1 M) and extracted with CH₂Cl₂. The combined organic layers were washed with HCl (aq, 1 M), sat'd. NaHCO₃, brine, dried (MgSO₄), filtered and concentrated in vacuo and purified by chromatography (SiO2, Acetone/Hexane 1:5) to yield 20.06 as a colorless solid.

Step 2

A solution of methyl ester 20.06 (4.0 g, 10.46 mmol) was dissolved in 4M HCl in dioxane and stirred at rt. for 3 h. The reaction mixture was concentrated in vacuo to obtain the amine hydrochloride salt, 20.07 which was used without purification.

Step 3

A solution of the amine salt 20.07 (840 mg, 2.64 mmol) in THF (14 mL)/acetonitrile (2 mL) was cooled to 0° C. 4-Nitrophenylchloroformate (800 mg, 3.96 mmol) was added followed by pyridine (0.64 mL, 7.92 mmol). The reaction was slowly warmed to room temperature over 3 hrs when TLC indicated reaction completion. Diethyl ether (50 mL) was added and the resulting precipitate was filtered off. The filtrate was washed with saturated ammonium chloride solution (1×), brine (1×), dried (Na₂SO₄) and concentrated. The residue was purified by flash chromatography using 20/80 EtOAc/hexanes which afforded 1.15 g of the required intermediate 20.08.

Preparation of Intermediate 21.01

Step 1

To a stirred solution of N-Boc-3,4-dehydroproline 21.02 (5.0 g, 23.5 mmol), di-tert-butyl dicarbonate (7.5 g, 34.4 mmol), and 4-N,N-dimethylaminopyridine (0.40 g, 3.33 mmol) in acetonitrile (100 mL) at room temperature was added triethylamine (5.0 mL, 35.6 mmol). The resulting solution was stirred at this temperature for 18 h before it was concentrated in vacuo. The dark brown residue was purified by flash column chromatography eluting with 10-25% EtOAc/hexane to give the product 21.03 as a pale yellow oil (5.29 g, 84%).

Step 2

To a stirred solution of the dehydroproline derivative 21.03 (10.1 g, 37.4 mmol), benzyltriethylammonium chloride (1.60 g, 7.02 mmol) in chloroform (120 mL) at room temperature was added 50% aqueous sodium hydroxide (120 g). After vigorously stirred at this temperature for 24 h, the dark mixture was diluted with CH₂Cl₂ (200 mL) and diethyl ether (600 mL). After the layers were separated, the aqueous solution was extracted with CH₂Cl₂/Et₂O (1:2, 3×600 mL). The organic solution was dried (MgSO₄) and concentrated. The residue was purified by flash column chromatography using 5-20% EtOAc/hexane to afford 9.34 g (71%) of 21.04 as an off-white solid.

Step 3

The solution of 21.04 (9.34 g, 26.5 mmol) in CH₂Cl₂ (25 mL) and CF₃CO₂H (50 mL) was stirred at room temperature for 4.5 h before it was concentrated in vacuo to give a brown residue, 21.05 which was used in Step 4 without further purification.

Step 4

Concentrated hydrochloric acid (4.5 mL) was added to a solution of the residue 21.05 from Step 3 in methanol (70 mL) and the resulting mixture was warmed to 65° C. in an oil bath. After 18 h, the mixture was concentrated in vacuo to give a brown oil 21.01, which was used further without purification.

Preparation of Intermediate 22.01

Step 1

Potassium bis(trimethylsilyl)amide (158 ml of a 0.5M solution in toluene; 79 mmol) was added to a stirred suspension of cyclopropyltriphenylphosphonium bromide (33.12 g; 86.4 mmol) in anhydrous tetrahydrofuran (130 ml) and the resulting orange mixture was stirred under an atmosphere of nitrogen at room temperature for a period of 1 h., before the addition of the aldehyde 22.02 (9.68 g; 42.2 mmol) in THF (8 ml). The reaction was then refluxed under an atmosphere of nitrogen for a period of 2 h. After cooling, methanol, diethyl ether and Rochelles salt were added. The organic phase was separated, washed with brine, dried and concentrated under reduced pressure. The crude reaction product was purified by silica gel column chromatography using EtOAc-hexane (1:99) to EtOAc-hexane (5:95) to provide the alkene 22.03 (8.47 g) as a yellow oil.

Step 2

A solution of 1M HCl in MeOH/MeOAc was prepared by adding 14.2 ml of acetyl chloride dropwise into cold methanol and diluting the resulting solution to 200 ml at room temperature.

The carbamate 22.03 (9.49 g; 37.5 mmol) was dissolved in methanol (12 ml) and added to 1M HCl in MeOH/MeOAc (150 ml) while cooled in an ice bath. The resulting mixture was maintained at this temperature for 1 h., then the ice bath was removed and stirring continued overnight at room temperature. The volatiles were removed under reduced pressure to yield a yellow oil which was used in the next step without purification.

The yellow oil was dissolved in a mixture of THF (30 ml) and MeOH (20 ml) and treated with triethylamine (15 ml; 108 mmol) until the solution was pH=9-10. After placing in an ice bath, the mixture was treated with N-Boc-Gly-OSu (11.22 g; 41 mmol). The ice bath was withdrawn and the reaction stirred at room temp. for 1 h. The volatiles were removed under reduced pressure and the residue was purified by silica gel column chromatography using methanol (1-3%) in dichloromethane providing the desired amide 22.04 (9.09 g).

Step 3

The alcohol 22.04 (9.09 g; 33.6 mmol) was dissolved in acetone (118.5 ml) and treated with 2,2-dimethoxypropane (37.4 ml; 304 mmol) and BF₃:Et₂O (0.32 ml; 2.6 mmol) and the resulting mixture was stirred at room temperature for a period of 5.5 h The reaction solution was treated with a few drops of triethylamine and the volatiles were removed under reduced pressure. The residue was purified by silica gel column chromatography using 5-25% EtOAc in hexanes to provide the N,O-acetal 22.05 (8.85 g).

Step 4

The carbamate 22.05 (8.81 g; 28.4 mmol) was dissolved in acetonitrile (45 ml) and the solution was cooled to −40° C. under an atmosphere of nitrogen. Pyridine (6.9 ml; 85.3 mmol) followed by nitrosium tetrafluoroborate (6.63 g; 56.8 mmol) were added and the resulting reaction mixture maintained below 0° C. until TLC indicated that no starting material remained (approx. 2.25 h.). Pyrrolidine (20 ml; 240 mmol) was added and the cooling bath was withdrawn and stirring was continued at room temperature for 1 h. and then the volatiles were removed under reduced pressure. The residue was quickly passed through a pad of silica gel to provide a yellow oil.

The yellow oil was dissolved in anhydrous benzene (220 ml) and palladium acetate (0.317 g; 1.41 mmol) was added before heating the resulting mixture to reflux, under an atmosphere of nitrogen for a period of 1.5 h. After cooling, the volatiles were removed under reduced pressure and the dark residue was purified by silica gel column chromatography using EtOAc-hexane (1:4) to provide the i) the trans-pyrrolidinone 22.06 (1.94 g) followed by ii) the cis-pyrrolidinone 22.07 (1.97 g).

Step 5

Freshly prepared 1M HCl in MeOAc/MeOH (10 ml; as described above) was added to the N,O-acetal 22.06 and stirred at room temperature for 1 h. The solvent was removed under reduced pressure and the residue was purified by silica gel column chromatography using 0-4% MeOH in dichloromethane as eluent to provide the desired alcohol 22.08 (1.42 g), a yellow oil.

Step 6

To a solution of the lactam 22.08 (1.29 g; 8.44 mmol) in anhydrous tetrahydrofuran (55 ml) was added lithium aluminum hydride (2.40 g; 63.2 mmol) and the resulting mixture was refluxed for 8 h. After cooling, water, followed by 15% aq. NaOH were added and the resulting mixture was filtered through celite and the solid was washed thoroughly with THF and MeOH. The solvent was removed under reduced pressure and the residue redissolved in dichloromethane, dried and concentrated under reduced pressure to provide the pyrrolidine, used without purification.

Hunigs base (4.5 ml; 25.8 mmol) was added to a mixture of N-Boc-L-tert-Leu-OH (1.76 g; 7.6 mmol), The crude pyrrolidine and HATU (2.89 g; 7.6 mmol) in anhydrous dichloromethane (50 ml) at −60° C., under an atmosphere of nitrogen. The resulting reaction was allowed to come to room temperature slowly, overnight. EtOAc was added and the yellow solution was washed with dil. aq. HCl, sat. aq. sodium bicarbonate, water, brine. The organic layer was dried and concentrated under reduced pressure. The residue was purified by silica gel column chromatography using EtOAc:hexanes (1:3) to give the desired amide 22.09 (2.00 g).

Step 7

The alcohol 22.09 (2.00 g; 5.67 mmol) was dissolved in acetone (116 ml) and cooled in an ice bath for 10 min. This solution was then added to a cooled Jones reagent (14.2 ml; approx 2 mmol/ml) and the resulting mixture was stirred at 5 C for 0.5 h and the cooling bath was removed. The reaction was stirred for a further 2 h. at room temp., before adding to sodium sulfate (28.54 g), celite (15 g) in EtOAc (100 ml). Isopropanol (15 ml) was added after 1 min and then stirred for a further 10 min. and filtered. The filtrate was concentrated under reduced pressure, providing a brown oil which was dissolved in EtOAc. This solution was washed with water, 3% aq. citric acid, brine, dried and concentrated to provide the desired carboxylic acid 22.01 (1.64 g) as a white solid.

Preparation of Intermediate 23.01

Step 1

To the mixture of ester 23.02 (6.0 g) and molecular sieve (5.2 g) in anhydrous methylene chloride (35 mL) was added pyrrolidine (5.7 mL, 66.36 mmoL). The resulting brown slurry was stirred at room temperature under N₂ for 24 h, filtered and washed with anhydrous CH₃CN. The combined filtrate was concentrated to yield the desired product, 23.03.

Step 2

To a solution of the product 23.03 from proceeding step in CH₃CN (35 mL) was added anhydrous K₂CO₃, methallyl chloride (2.77 g, 30.5 mmoL), NaI (1.07 g, 6.7 mmoL). The resulting slurry was stirred at ambient temperature under N₂ for 24 h. 50 mL of ice-cold water was added followed by 2N KHSO₄ solution until pH was 1. EtOAc (100 mL) was added and the mixture was stirred for 0.75 h. Combined organic layer was collected and washed with brine, dried over MgSO₄, and evaporated to yield the desired product, 23.04.

Step 3

The product 23.04 from the preceding step (2.7 g, 8.16 mmoL) was dissolved in dioxane (20 mL) and treated with freshly prepared 1N LiOH (9 mL). The reaction mixture was stirred at ambient temperature under N₂ for 20 h. The reaction mixture was taken in EtOAc and washed with H₂O. The combined aqueous phase was cooled to 0° C. and acidified to pH 1.65 using 1N HCl. The turbid mixture was extracted with EtOAc (2×100 mL). Combined organic layer was washed with brine, dried over MgSO₄, and concentrated to give the desired acid, 23.05 (3.40 g).

Step 4

To a suspension of NaBH(OAc)₃ (3.93 g, 18.5 mmoL) in CH₂Cl₂ (55 mL) was added a solution of product 23.05 from preceding step in anhydrous CH₂Cl₂ (20 mL) and acetic acid (2 mL). The slurry was stirred at ambient temperature for 20 h. Ice cold water (100 mL) was added to the slurry and stirred for ½ hr. Organic layer was separated, filtered, dried and evaporated to yield the desired product, 23.06.

Step 5

To a solution of the product 23.06 from preceding step (1.9 g) in MeOH (40 mL) was treated with excess of CH₂N₂/Et₂O solution and stirred for overnight. The reaction mixture was concentrated to dryness to yield a crude residue. The residue was chromatographed on silica gel, eluting with a gradient of EtOAc/hexane to afford 1.07 g of the pure desired product, 23.07.

Step 6

To a solution of product 23.07 from preceding step (1.36 g) in anhydrous CH₂Cl₂ (40 mL) was treated with BF₃. Me₂O (0.7 mL). The reaction mixture was stirred at ambient temperature for 20 h and quenched with sat. NaHCO₃ (30 mL) ad stirred for ½ hr. Organic layer was separated and combined organic layer was washed with brine, dried over MgSO₄, concentrated to give crude residue. The residue was chromatographed on silica gel eluting with a gradient of EtOAc/hexane to afford 0.88 g of the desired compound, 23.08.

Step 7

To a solution of the product 23.08 (0.92 g) from preceding step in MeOH (30 mL) was added 10% Pd/C (0.16 g) at room temperature and hydrogenated at ambient temperature under 1 atm. Pressure. The reaction mixture was stirred for 4 h and concentrated to dryness to yield the desired compound, 23.01.

Preparation of P₃ Moieties Preparation of Intermediate 50.01

Step 1

To a solution of 50.02 (15 g) in MeOH (150 mL) was added conc HCl (3-4 mL) and the mixture was refluxed for 16 h. The reaction mixture was cooled to room temperature and concentrated. The residue was taken in diethyl ether (250 mL) and washed with cold saturated sodium bicarbonate solution, and brine. The organic layer was dried (Na₂SO₄) and concentrated to afford the methyl ester 50.03 (12.98 g) which was carried forward without further purification.

Step 2

The methyl ester 50.03 from above was dissolved in methylene chloride (100 mL) and cooled to −78° C., under nitrogen atmosphere. DIBAL (1.0 M solution in methylene chloride, 200 mL) was added dropwise over 2 h period. The reaction mixture was warmed to room temperature over 16 h. The reaction mixture was cooled to 0° C. and MeOH (5-8 mL) was added dropwise. A solution of aqueous 10% sodium potassium tartarate (200 mL) was slowly added with stirring. Diluted with methylene chloride (100 mL) and separated the organic layer (along with some white precipitate). The organic layer was washed with 1 N HCl (250 mL), brine (200 mL), dried (Na₂SO₄) and concentrated to provide the alcohol 50.04 (11.00 g) as a clear oil.

Step 3

The alcohol 50.04 from above was dissolved in methylene chloride (400 mL) and cooled to 0° C. under nitrogen atmosphere. PCC (22.2 g) was added in portions and the reaction mixture was slowly warmed to room temperature over 16 h. The reaction mixture was diluted with diethyl ether (500 mL) and filtered through a pad of celite. The filtrate was concentrated and the residue was taken in diethyl ether (500 mL). This was passed through a pad of silica gel and the filtrate was concentrated to provide the aldehyde 50.05 which was carried forward without further purification.

Step 4

The aldehyde 50.05 from above was converted to the desired material 50.01 using essentially the method of Chakraborty et. al (Tetrahedron, 1995, 51(33), 9179-90).

Preparation of Intermediate 51.01

The required intermediate 51.01 was obtained from the aldehyde 51.02 using the literature described procedure (T. K. Chakraborty et al., Tetrahedron, 1995, 51 (33), 9179-90).

PREPARATION OF SPECIFIC EXAMPLES Preparation of Example 1007

Step 1

Commercially available compound 1007a (Aldrich Chemical Co., Milwaukee, Wis., USA) was converted to 1007b according to the literature procedure (M. E. Duggan, J. S. Imagire Synthesis 1989, 131-2) in 90% yield. LC-MS: 289 (M+H).

Step 2

Deprotection of 1007b using 4M HCl in dioxane at room temperature for 3 hrs provided 1007c in quantitative yield. This material was used without further purification.

Step 3

Compound 1007d was obtained from appropriate starting materials/reagents using the previously described procedures (See preparation of Intermediate 20.08).

To a solution of 1007d (200 mg, 0.394 mmol) in dichloromethane (10 mL) at 0° C., under nitrogen atmosphere, was added 1007c (115 mg, 0.512 mmol) followed by DIPEA (0.22 mL, 1.182 mmol). The reaction was maintained at that temperature for 30 min and stored in the freezer (−20° C.) for 48 hrs. The reaction mixture was quenched with saturated ammonium chloride solution and the product was extracted into dichloromethane (3×). The combine organic layers was washed with brine (1×), dried (Na₂SO₄), filtered and concentrated. The crude residue was purified by flash chromatography using 30/70 acetone/hexanes which provided the required compound 1007e in 69% yield. LC-MS: 557 (M+H).

Step 4

Hydrolysis of the methyl ester of 1007e to provide the required acid 1007f was carried out as described before (see preparation of Intermediate 20.04, Step 2) with appropriate modifications.

Step 5

Coupling reaction of the acid 1007f (0.125 mmol) with the amine salt 10.11 was carried out as described before (see preparation of Intermediate 20.08, Step 1) with modifications (HATU instead of BOP, DIPEA instead of NMM; the reaction was carried out at 0° C. for 15 min and warmed to 10° C. over 24 hrs) and appropriate amounts of the reagents. The crude material obtained after workup, 1007g was carried forward without purification. LC-MS: 697.2 (M+H).

Step 6

To a cold (0° C.) solution of the material from above, 1007g (0.125 mmol) in DMSO/toluene (3 mL each) was added EDCI (240 mg, 1.25 mmol) followed by dichloroacetic acid (0.052 mL, 0.625 mmol). After 15 min, the cold bath was removed and the reaction mixture was warmed to room temperature over 16 hr. The reaction mixture was diluted with EtOAc (20 mL) and washed with aqueous 1N NaHSO₄ (20 mL). The aqueous layer was separated and extracted with EtOAc (20 mL). The combined organic layers was washed with aqueous 1N NaHSO₄ (20 mL), saturated NaHCO₃ (20 mL), brine (20 mL), dried (Na₂SO₄), filtered and concentrated in vacuo. The crude residue was purified by flash column chromatography using 40/60 acetone/hexanes to provide the required target compound 1007 (57 mg, 0.082 mmol, 66% yield). LC-MS: 695.2 (M+H).

Preparation of Example 1044

Step 1

Coupling reaction of the acid 1044a, obtained in a similar manner as described for 1007f (see preparation of Example 1007), with the amine salt 14.01 was carried out as described before (see preparation of Example 1007, Step 5). The crude material obtained after workup, 1044b was carried forward without purification. LC-MS: 725.2 (M+H).

Step 2

To a solution of the material from above, 1044b (0.054 mmol) in dichloromethane (5 mL) was added Dess-Martin's periodinane (68 mg, 0.16 mmol). The reaction mixture was stirred at room temperature, under nitrogen atmosphere, for 4.5 hrs. The reaction mixture was diluted with dichloromethane (10 mL) and washed with aqueous 10% Na₂S₂O₃ (30 mL), saturated NaHCO₃ (30 mL), brine (30 mL), dried (Na₂SO₄), filtered and concentrated in vacuo. The crude residue was purified by flash column chromatography using 35/65 acetone/hexanes to provide the required target compound 1044 (23 mg, 0.032 mmol, 59% yield). LC-MS: 723.2 (M+H).

Compounds in the following Table 1 and Table 1A were essentially prepared using the above-described procedures (Preparation of Examples 1007 and 1044) with appropriate reagents and modifications as described in the General Schemes for Preparation of Target Compounds, Methods A-E.

TABLE 1 Example Ki* Mol # Structure (nM) Weight 1001

A 696.885 1002

A 662.868 1003

A 648.841 1004

A 682.859 1005

A 634.815 1006

A 668.832 1007

A 694.87  1008

A 680.843 1009

A 694.87  1010

A 708.896 1011

A 734.934 1012

A 722.923 1013

A 694.87  1014

A 708.896 1015

A 776.895 1016

A 696.885 1017

A 662.868 1018

A 676.895 1019

A 632.799 1020

A 646.826 1021

A 660.852 1022

A 720.907 1023

A 708.896 1024

A 680.843 1025

A 694.87  1026

A 762.868 1027

A 646.826 1028

A 660.852 1029

A 674.879 1030

A 748.961 1031

A 736.95  1032

A 708.896 1033

A 722.923 1034

A 694.87  1035

A 680.843 1036

A 668.832 1037

B 708.896 1038

B 720.907 1039

A 706.881 1040

A 694.87  1041

A 666.816 1042

A 680.843 1043

A 708.896 1044

A 722.923 1045

A 736.95  1046

A 750.977 1047

A 748.841 1048

A 674.879 1049

A 688.906 1050

B 686.89  1051

A 648.841 1052

A 620.788 1053

A 634.815 1054

A 646.826 1055

A 660.852 1056

A 688.906 1057

A 702.933 1058

A 674.879 1059

A 634.815 1060

A 606.761 1061

A 620.788 1062

B 726.912 1063

B 740.938 1064

B 696.885 1065

A 720.907 1066

A 706.881 1067

A 696.885 1068

B 724.939 1069

B 754.965 1070

A 734.934 1071

A 710.912 1072

A 710.912 1073

A 718.892 1074

B 724.939 1075

A 648.841 1076

A 634.815 1077

A 620.788 1078

B 694.87  1079

A 720.907 1080

A 668.832 1081

A 660.852 1082

A 646.826 1083

A 728.851 1084

A 686.89  1085

A 688.906 1086

A 684.874 1087

A 674.871 1088

A 660.844 1089

A 702.924 1090

A 698.892 1091

A 686.882 1092

A 688.898 1093

A 700.908 1094

A 688.898 1095

A 712.919 1096

A 716.951 1097

A 702.924 1098

A 714.935 1099

A 714.935 1100

A 700.908 1101

A 710.903

TABLE 1A Example Ki* LC-MS # Structure (nM) (M + H) 1102

A 729.2 1103

B 715.2 1104

A 725.2 1105

A 727.2 1106

A 731.2 1107

A 717.2 1108

A 727.2 1109

A 729.2 1110

B 772.2 1111

B 757.2 1112

A 767.2 1113

B 769.4 1114

A 715.2 1115

A 724.939 1116

A 729.2 1117

A 727.2 1118

A 711.2 1119

B 701.2 1120

A 741.2 1121

A 741.4 Ki* range: A = <75 nM, B = 75–250 nM; C = >250 nM

Preparation of Example 1441

Step 1

To a ice cooled solution of 1441a (4.28 g, 10.08 mmol) in anhydrous ether (100 mL) was added LAH (1.53 g, 40.32 mmol) and the reaction mixture was allowed to warm to room temperature overnight. The reaction mixture was cooled to 0° C. and EtOAc (3 mL) was added to it, followed by aqueous KHSO₄ (10 g in 25 mL of H₂O). The gummy residue was extracted with ether (300 mL) and the organic layer was washed with satd. NaHCO₃, followed by 10% aq. KH₂PO₄, brine, dried over MgSO₄, filtered and concentrated. The crude residue was purified by flash chromatography over SiO₂ using ethyl acetate/DCM (1:4) to yield 1441b (2.14 g, 92%).

Step 2

To a ice cooled solution of 1441b (743 mg, 3.24 mmol) in anhydrous pyridine (10 mL) was added methyl chloroformate (1 mL, 13 mmol), followed by DMAP (1.6 g, 13 mmol) and the reaction mixture was allowed to warm to room temperature over 2 days. The reaction mixture was concentrated and EtOAc (100 mL) was added to it followed by 100 mL of ice-cold (5% KH₂PO₄ containing 0.05 volumes of 1M H₃PO₄). The organic layer was washed with brine and dried over MgSO₄, filtered and concentrated. The crude was purified by flash chromatography over SiO₂ using ethyl acetate/DCM (1:4) to yield 1441c (931 mg, 100% yield).

Step 3

1441c was dissolved in 4M HCl in dioxane (10 mL) and concentrated after 30 min. Saturated NaHCO₃ (25 mL) was added to an ice-cold solution of the crude hydrochloride salt (194 mg, 1 mmol) in CH₂Cl₂ (25 mL). The reaction mixture was stirred vigorously for 10 min and COCl₂ (1.85 M solution in PhMe, 4 mL) was added to it and stirring was continued at room temperature for 1 h. The organic layer was separated, dried over MgSO₄, filtered and concentrated to half the volume to yield 1441d as a 0.05 M solution in CH₂Cl₂.

Step 4

To a −20° C. solution 1.17 (10.4 g, 28 mmol; obtained by the hydrolysis of 20.06 using the procedure described for Intermediate 20.04, Step 2) in DCM (300 mL) was added HATU (1.05 equiv, 29.4 mmol, 11.2 g), amine salt, Intermediate 12.03 (1.0 equiv, 28 mmol, 5.48 g). After 10 min at −20° C., DIPEA (3.6 equiv, 100 mmol, 17.4 mL) was added. Reaction was stirred at this temp for 16 hr. After 16 hr, the reaction was diluted with EtOAc and washed successively with NaHCO₃, citric acid (10% w/w) and brine. Organic layer was dried over MgSO₄, filtered and concentrated in vacuo to yield 14 g of the required intermediate 1441e.

Step 5

The hydroxyamide 1441e was oxidized to the required ketoamide 1441f in a manner described for Example 1007, Step 6. LC-MS=507 (M+H)⁺

Step 6

Deprotection of the t-Boc functionality of 1441f to give the required material 1441g was carried out as described for Example 1007, Step 2.

Step 7

To a cooled solution (0° C.) of the amine hydrochloride 1441g (20 mg, 0.045 mmol) in CH₂Cl₂ (2.0 mL) was added 1441d (1.35 mL, 0.135 mmol), followed by DIPEA (63 μL, 0.4 mmol). The reaction mixture was stirred at room temperature for 1.2 h, diluted with ethyl acetate (20 mL), washed with 3% citric acid, brine, dried over MgSO₄, filtered, concentrated and purified over SiO₂ using EtOAc/DCM (1:9 to 9:1) to yield 1441 (23 mg). LCMS=620.3 (M+H)⁺.

Compounds in the following table (Table 2) were essentially prepared using the above described procedures (Preparation of Example 1441) with appropriate reagents and modifications as described in the General Schemes for Preparation of Target Compounds, Methods A-E.

TABLE 2 Example Ki* Mol # Structure (nM) Weight 1401

A 669.817 1402

A 683.843 1403

B 697.87 1404

A 649.826 1405

A 663.853 1406

B 677.88 1407

A 633.784 1408

A 647.81 1409

B 661.837 1410

A 635.799 1411

A 649.826 1412

A 663.853 1413

A 593.719 1414

A 621.773 1415

A 647.81 1416

A 621.773 1417

A 649.826 1418

A 675.864 1419

A 607.746 1420

A 621.773 1421

A 635.799 1422

C 689.891 1423

B 647.81 1424

A 607.746 1425

A 635.799 1426

A 661.837 1427

A 661.837 1428

A 619.757 1429

A 675.864 1430

A 633.784 1431

B 709.881 1432

A 645.795 1433

A 659.821 1434

B 673.848 1435

B 695.854 1436

A 605.73 1437

A 619.757 1438

B 633.784 1439

B 723.908 1440

B 647.81 1441

A 619.757 1442

A 633.784 1443

B 675.864 1444

A 647.81 1445

A 661.837 1446

B 687.875 1447

A 659.821 1448

A 673.848 Ki* range A = <75 nM; B = 75–250 nM, C = >250 nM

Preparation of Example 1655

Step 1

To a solution of commercially available compound 1655a (Aldrich Chemical Co., Milwaukee, Wis., USA, 950 mg, 4.38 mmol) in acetonitrile (40 mL) at room temperature was added methyl iodide (4.63 mL, 74.42 mmol). Silver(I) oxide (1.62 g, 7.01 mmol) was then added under nitrogen atmosphere and the reaction mixture was refluxed for approximately 16 hrs. (Note: The reaction flask was covered with aluminum foil). At this time, the reaction mixture was cooled to room temperature and filtered through a pad of celite. The filter cake was rinsed with ethyl acetate several times. The combined filtrate was concentrated and purified by flash column chromatography using 20/80 to 40/60 ethyl acetate/hexanes to afford 720 mg of the expected product, 1655b.

Step 2

Conversion of 1655b to compound 1655c proceeded in quantitative yield using previously described procedure (Step 2, Example 1007).

Step 3

To a solution of compound 1655c (514 mg, 3.08 mmol) in dichloromethane (20 mL) was added saturated sodium bicarbonate solution (20 mL). This mixture was stirred vigorously and cooled to 0° C. Phosgene (20 wt % in toluene, 6.5 mL) was added dropwise. The reaction mixture was stirred vigorously for 4.5 hrs while maintaining the temperature at or below 5° C. At this time the reaction mixture was poured into a separatory funnel and the organic layer was separated. The organic layer was washed with saturated ammonium chloride solution (1×), water (1×), dried (Na₂SO₄) and concentrated. The residue, 1655d, was diluted with dichloromethane (10 mL) and used further as a 0.308M solution.

Step 4

To a cold (0° C.) solution of 1655e (176 mg, 0.5 mmol; 1655e was prepared as described for Intermediate 20.08, Steps 1 and 2 using appropriate starting materials) in dichloromethane (4 mL) was added 1655d (0.308 M solution, 4.87 mL, 1.5 mmol) followed by DIPEA (0.276 mL, 1.5 mmol). The reaction mixture was maintained at 10° C. for 16 hrs. The reaction was quenched with saturated ammonium chloride solution and the aqueous layer was extracted with dichloromethane (3×). The combined organic layer was washed with brine, dried (Na₂SO₄), filtered and concentrated in vacuo. The crude residue was purified by flash column chromatography using 20/80 acetone/hexanes to provide the required compound 1655f (240 mg, 100% yield). LC-MS: 480.1 (M+H).

Step 5

Compound 1655f from above was converted to the required target compound 1655 using the intermediate 10.11 and procedures described above (Steps 4-6, Example 1007). LC-MS of 1655=618.1 (M+H).

Preparation of Example 1614

Step 1

To a stirred solution of N-Boc-tert-leucinol 1655a (2.0 g, 9.22 mmol), phenol (1.0 g, 10.6 mmol) and ADDP (3.8 g, 15.1 mmol) in CH₂Cl₂ (80 mL) at rt was bubbled argon gas for 15 min. Triphenylphosphine was then added in one portion. The resulting solution was stirred at RT for 18 h. The precipitates were filtered off and washed with diethyl ether (2×30 mL). The filtrate was concentrated in vacuo. The residue was purified by flash column chromatography eluting with 2-10% EtOAc/hexane to give the desired product 1614a (0.33 g, 12%).

Step 2

Compound 1614a (0.32 g, 1.13 mmol) was dissolved in a 4 M hydrogen chloride solution in p-dioxane (20 mL) and stirred at RT for 3 h. It was concentrated in vacuo to give compound 1614b, which was used without further purification.

Step 3

Compound 1614c was prepared from 1614b according to the procedures described for Example 1655, Step 3.

Step 4

The isocyanate 1614c was converted to the target compound 1614 as described in the General Schemes, Method C using the appropriate reagents and Intermediates.

Preparation of Example 1610

Step 1

To a stirred suspension of anhydrous magnesium sulfate in anhydrous CH₂Cl₂ (40 mL) at RT was added concentrated sulfuric acid (0.32 mL, 5.76 mmol). The mixture was vigorously stirred for 30 min before a solution of 1610a (2.0 g, 7.90 mmol) in anhydrous CH₂Cl₂ (15 mL) was added. The mixture was then vigorously stirred at RT for 68 h. Saturated NaHCO₃ solution (50 mL) was added cautiously, along with CH₂Cl₂ (100 mL) and water (50 mL). Two phases were separated, and the aqueous layer was extracted with CH₂Cl₂ (2×100 mL). The combined organic solution was dried (MgSO₄), filtered and concentrated in vacuo to give 1610b.

Step 2

A suspension of compound 1610b and 10% Pd—C in absolute ethanol was vigorously stirred under a hydrogen atmosphere for 4 h. The catalyst was filtered off through a celite pad. The filtrate was concentrated in vacuo to afford 1610c which was used without further purification.

Step 3

Compound 1610d was prepared from 1610c according to the procedures described for Example 1655, Step 3.

Step 4

The isocyanate 1610d was converted to the target compound 1610 as described in the General Schemes, Method C using the appropriate reagents and Intermediates.

Preparation of Example 1620

Step 1

A suspension of the alcohol 1655a (3.46 g, 12.8 mmol), benzyl bromide (10 mL, 84.2 mmol) and silver(I) oxide (5.0 g, 21.6 mmol) in acetonitrile was stirred vigorously at 76° C. in an oil bath overnight (18 h), The solid material was filtered off and the solution was concentrated in vacuo. The product was purified by flash column chromatography eluting with 5-40% EtOAc/hexane to give the desired product 1620a (0.78 g, 20%).

Step 2

Compound 16120b was prepared from 1620a according to the procedures described for Example 1614, Step 2.

Step 3

Compound 1620c was prepared from 1620b according to the procedures described for Example 1655, Step 3.

Step 4

The isocyanate 1620c was converted to the target compound 1620 as described in the General Schemes, Method C using the appropriate reagents and Intermediates.

Preparation of Example 1629

Step 1

To 1441e (600 mg) was added 4M HCl in dioxane (25 mL). The reaction was stirred at room temperature for 30 min. and concentrated to yield a white solid, 1629a (490 mg), which was carried forward without purification.

Step 2

To a cooled (0° C.) solution of compound 1629a (395 mg) in CH₂Cl₂ (25 mL) was added Et₃N (0.57 mL), followed by the isocyanate 1629b (Robinson, Ralph P.; Marfat, Anthony. Eur. Pat. Appl. (1991), EP 436333 A2 19910710, 53 pp) in a manner described above (Example 1655, Step 4). The crude hydroxyamide obtained was used without purification.

A solution of the crude hydroxyamide in toluene-DMSO (2.0 mL each) was cooled to 0° C. To the reaction mixture was added EDCI.HCl (410.0 mg), followed by dichloroacetic acetic (0.087 mL), after stirring for 2 h at room temperature, it was diluted with EtOAc, washed with 1N HCl, satd. NaHCO₃, brine, dried over MgSO4, filtered, concentrated to yield a white solid which was purified by chromatography over silica gel using acetone-hexane (40:60) to afford the title compound 1629 (280.0 mg) as a white solid: Mass spectrum for C33H49N5O6 (611.77); found FAB (M+H)⁺=612.5

Preparation of Example 1628

To a solution of compound 1629 (37.0 mg) in MeOH (2.0 mL) was added Pd—C (10% w/v, 5.0 mg) and the reaction was stirred under hydrogen atmosphere for 1 h, filtered through a pad of celite, concentrated and purified by chromatography over silica gel using acetone-hexane (4:6) to yield the required compound 1628 (22.0 mg) as a white solid. Mass spectrum for C26H43N5O6 (521.65); found FAB (M+H)⁺=522.6.

Preparation of Example 1633

The required title compound 1633 was obtained from the isocyanate 1629b and compound 1633a (prepared from 1.17 and 10.11) using procedures described for Example 1629. Mass spectrum for C34H51N5O6 (625.80); found FAB (M+H)⁺=626.8.

Preparation of Example 1632

To a solution of compound 1633 (10.0 mg) in MeOH (2.0 mL) was added Pd—C (10% w/v, 2.0 mg) and the reaction was stirred under hydrogen atmosphere for 1 h, filtered through a pad of celite, concentrated and purified by chromatography over silica gel using acetone-hexane (4:6) to yield the title compound 1632 as a white solid (4.2 mg). Mass spectrum for C27H45N5O6 (535.68); found FAB (M+H)⁺=536.7.

Preparation of Example 1647

Step 1

To a stirred solution of the commercially available compound 1647a (Aldrich Chemical Co., Milwaukee, Wis., USA, 250.0 mg) in MeOH was added trimethylsilyl diazomethane (2.0 mL, 2M solution in PhMe). After 20 min the solvent was removed and the crude was redissolved in CH₂Cl₂ (2.0 mL) and Benzyloxymethyl chloride (1.5 equivalent) was added along with Et₃N (1.5 equivalent). The reaction mixture was stirred overnight, diluted with EtOAc, washed successively with 5% Na₂S₂O₃, satd. NaHCO₃, 1N HCl, brine, dried over MgSO4, filtered, concentrated to yield a white solid which was purified by chromatography over silica gel using EtOAc-hexane (1:3) to afford the compound 1647b (413 mg) as a white solid: Mass spectrum for C20H24O4 (328.40); found FAB (M+H)⁺=329.4.

Step 2

To a solution of 0.413 g of compound 1647b in MeOH/H₂O (5.0/0.5 mL) was added 0.735 g of KOH. The reaction mixture was refluxed overnight, cooled to room temperature and concentrated. The crude was redissolved in H₂O (10.0 mL) and acidified with 10% aqueous HCl and extracted with CH₂Cl₂, dried over MgSO₄, filtered and concentrated to afford the corresponding carboxylic acid 1647c (392 mg). The crude was directly used in the next step. To a solution of 123.2 mg of acid 1647c in toluene (5.0 mL) was added DPPA (0.09 mL) and Et₃N (0.055 mL). The reaction mixture was heated at 110° C. for 40 min, cooled and washed with satd. NaHCO₃, dried over MgSO₄, filtered and concentrated to afford the isocyanate 1647d. The crude obtained was used without purification.

Step 3

The isocyanate 1647d was treated with compound 1629a (90.0 mg) in a manner described in Example 1629 to provide the title compound 1647. Mass spectrum for C40H55N5O7 (717.89); found FAB (M+H)⁺=718.8.

Preparation of Example 1648

To a solution of compound 1647 in MeOH was added 6N HCl after 30 min, the MeOH was removed and the crude was redissolved in ethyl acetate and washed with satd. NaHCO₃. The crude was purified by chromatography over silica gel using acetone-hexane (40:60) to afford the title compound 1648 (25.0 mg) as a white solid: Mass spectrum for C32H47N5O6 (597.75); found FAB (M+H)⁺=598.7.

Compounds in the following table (Table 3) were essentially prepared using the above described procedures (Preparation of Examples 1610, 1614, 1620, 1628, 1629, 1632, 1633, 1647, 1648, 1655) with appropriate reagents and modifications as described in the General Schemes for Preparation of Target Compounds, Methods A-E.

TABLE 3 Example Ki* Mol # Structure (nM) Weight 1601

B 577.763 1602

B 563.736 1603

A 637.818 1604

A 547.693 1605

A 665.871 1606

A 651.845 1607

A 561.72 1608

B 679.855 1609

B 691.866 1610

A 619.843 1611

A 633.827 1612

A 647.854 1614

B 625.807 1616

C 663.856 1617

B 573.731 1618

B 639.834 1619

B 653.86 1620

B 639.834 1621

A 665.871 1622

C 725.926 1623

B 691.909 1624

A 601.785 1625

B 635.802 1626

A 575.747 1627

A 591.79 1628

A 521.656 1629

B 611.78 1630

A 623.791 1631

A 637.818 1632

A 535.682 1633

B 625.807 1634

B 743.942 1635

A 623.791 1636

B 673.935 1641

A 757.968 1642

A 637.818 1643

B 771.995 1644

A 651.845 1647

B 717.904 1648

B 597.753 1649

A 645.881 1650

B 631.854 1651

A 609.764 1652

A 623.791 1653

B 653.817 1654

A 603.801 1655

A 617.827 1656

A 589.774 1657

A 603.801 1658

B 611.78 1659

A 603.801 1660

A 589.774 1661

B 671.799 1662

B 629.838 1663

B 651.845 1664

B 663.856 1665

B 705.816 1666

A 611.78 1667

A 665.751 1668

B 653.86 1669

A 625.807 1670

A 589.774 1671

B 617.827 1672

A 603.801 1673

B 617.827 1674

B 603.801 1675

C 687.953 1676

B 683.921 1677

A 645.873 1678

B 659.899 1679

B 647.889 1680

A 695.932 1681

C 699.963 1682

B 671.910 1683

A 657.884 1684

B 659.899 1685

B 655.868 1686

C 659.899 1687

A 617.820 1688

A 631.846 Ki* range A = <75 nM; B = 75–250 nM; C = >250 nM

The present invention relates to novel HCV protease inhibitors. This utility can be manifested in their ability to inhibit the HCV NS2/NS4a serine protease. A general procedure for such demonstration is illustrated by the following in vitro assay.

Assay for HCV Protease Inhibitory Activity:

Spectrophotometric Assay: Spectrophotometric assay for the HCV serine protease can be performed on the inventive compounds by following the procedure described by R. Zhang et al, Analytical Biochemistry, 270 (1999) 268-275, the disclosure of which is incorporated herein by reference. The assay based on the proteolysis of chromogenic ester substrates is suitable for the continuous monitoring of HCV NS3 protease activity. The substrates are derived from the P side of the NS5A-NS5B junction sequence (Ac-DTEDVVX(Nva), where X=A or P) whose C-terminal carboxyl groups are esterified with one of four different chromophoric alcohols (3- or 4-nitrophenol, 7-hydroxy-4-methyl-coumarin, or 4-phenylazophenol). Illustrated below are the synthesis, characterization and application of these novel spectrophotometric ester substrates to high throughput screening and detailed kinetic evaluation of HCV NS3 protease inhibitors.

Materials and Methods:

Materials: Chemical reagents for assay related buffers are obtained from Sigma Chemical Company (St. Louis, Mo.). Reagents for peptide synthesis were from Aldrich Chemicals, Novabiochem (San Diego, Calif.), Applied Biosystems (Foster City, Calif.) and Perseptive Biosystems (Framingham, Mass.). Peptides are synthesized manually or on an automated ABI model 431A synthesizer (from Applied Biosystems). UV/VIS Spectrometer model LAMBDA 12 was from Perkin Elmer (Norwalk, Conn.) and 96-well UV plates were obtained from Corning (Corning, N.Y.). The prewarming block can be from USA Scientific (Ocala, Fla.) and the 96-well plate vortexer is from Labline Instruments (Melrose Park, Ill.). A Spectramax Plus microtiter plate reader with monochrometer is obtained from Molecular Devices (Sunnyvale, Calif.).

Enzyme Preparation: Recombinant heterodimeric HCV NS3/NS4A protease (strain 1a) is prepared by using the procedures published previously (D. L. Sali et al, Biochemistry, 37 (1998) 3392-3401). Protein concentrations are determined by the Biorad dye method using recombinant HCV protease standards previously quantified by amino acid analysis. Prior to assay initiation, the enzyme storage buffer (50 mM sodium phosphate pH 8.0, 300 mM NaCl, 10% glycerol, 0.05% lauryl maltoside and 10 mM DTT) is exchanged for the assay buffer (25 mM MOPS pH 6.5, 300 mM NaCl, 10% glycerol, 0.05% lauryl maltoside, 5 μM EDTA and 5 μM DTT) utilizing a Biorad Bio-Spin P-6 prepacked column.

Substrate Synthesis and Purification: The synthesis of the substrates is done as reported by R. Zhang et al, (ibid.) and is initiated by anchoring Fmoc-Nva-OH to 2-chlorotrityl chloride resin using a standard protocol (K. Barlos et al, Int. J. Pept. Protein Res., 37 (1991), 513-520). The peptides are subsequently assembled, using Fmoc chemistry, either manually or on an automatic ABI model 431 peptide synthesizer. The N-acetylated and fully protected peptide fragments are cleaved from the resin either by 10% acetic acid (HOAc) and 10% trifluoroethanol (TFE) in dichloromethane (DCM) for 30 min, or by 2% trifluoroacetic acid (TFA) in DCM for 10 min. The combined filtrate and DCM wash is evaporated azeotropically (or repeatedly extracted by aqueous Na₂CO₃ solution) to remove the acid used in cleavage. The DCM phase is dried over Na₂SO₄ and evaporated.

The ester substrates are assembled using standard acid-alcohol coupling procedures (K. Holmber et al, Acta Chem. Scand., B33 (1979) 410-412). Peptide fragments are dissolved in anhydrous pyridine (30-60 mg/ml) to which 10 molar equivalents of chromophore and a catalytic amount (0.1 eq.) of para-toluenesulfonic acid (pTSA) were added. Dicyclohexylcarbodiimide (DCC, 3 eq.) is added to initiate the coupling reactions. Product formation is monitored by HPLC and can be found to be complete following 12-72 hour reaction at room temperature. Pyridine solvent is evaporated under vacuum and further removed by azeotropic evaporation with toluene. The peptide ester is deprotected with 95% TFA in DCM for two hours and extracted three times with anhydrous ethyl ether to remove excess chromophore. The deprotected substrate is purified by reversed phase HPLC on a C3 or C8 column with a 30% to 60% acetonitrile gradient (using six column volumes). The overall yield following HPLC purification can be approximately 20-30%. The molecular mass can be confirmed by electrospray ionization mass spectroscopy. The substrates are stored in dry powder form under desiccation.

Spectra of Substrates and Products: Spectra of substrates and the corresponding chromophore products are obtained in the pH 6.5 assay buffer. Extinction coefficients are determined at the optimal off-peak wavelength in 1-cm cuvettes (340 nm for 3-Np and HMC, 370 nm for PAP and 400 nm for 4-Np) using multiple dilutions. The optimal off-peak wavelength is defined as that wavelength yielding the maximum fractional difference in absorbance between substrate and product (product OD−substrate OD)/substrate OD).

Protease Assay: HCV protease assays are performed at 30° C. using a 200 μl reaction mix in a 96-well microtiter plate. Assay buffer conditions (25 mM MOPS pH 6.5, 300 mM NaCl, 10% glycerol, 0.05% lauryl maltoside, 5 μM EDTA and 5 μM DTT) are optimized for the NS3/NS4A heterodimer (D. L. Sali et al, ibid.)). Typically, 150 μl mixtures of buffer, substrate and inhibitor are placed in wells (final concentration of DMSO≦4% v/v) and allowed to preincubate at 30° C. for approximately 3 minutes. Fifty μls of prewarmed protease (12 nM, 30° C.) in assay buffer, is then used to initiate the reaction (final volume 200 μl).The plates are monitored over the length of the assay (60 minutes) for change in absorbance at the appropriate wavelength (340 nm for 3-Np and HMC, 370 nm for PAP, and 400 nm for 4-Np) using a Spectromax Plus microtiter plate reader equipped with a monochrometer (acceptable results can be obtained with plate readers that utilize cutoff filters). Proteolytic cleavage of the ester linkage between the Nva and the chromophore is monitored at the appropriate wavelength against a no enzyme blank as a control for non-enzymatic hydrolysis. The evaluation of substrate kinetic parameters is performed over a 30-fold substrate concentration range (˜6-200 μM). Initial velocities are determined using linear regression and kinetic constants are obtained by fitting the data to the Michaelis-Menten equation using non-linear regression analysis (Mac Curve Fit 1.1, K. Raner). Turnover numbers (k_(cat)) are calculated assuming the enzyme is fully active.

Evaluation of Inhibitors and Inactivators: The inhibition constants (K_(i)) for the competitive inhibitors Ac-D-(D-Gla)-L-I-(Cha)-C—OH (27), Ac-DTEDVVA(Nva)-OH and Ac-DTEDVVP(Nva)-OH are determined experimentally at fixed concentrations of enzyme and substrate by plotting v_(o)/v_(i) vs. inhibitor concentration ([I]_(o)) according to the rearranged Michaelis-Menten equation for competitive inhibition kinetics: v_(o)/v_(i)=1+[I]_(o)/(K_(i)(1+[S]_(o)/K_(m))), where v_(o) is the uninhibited initial velocity, v_(i) is the initial velocity in the presence of inhibitor at any given inhibitor concentration ([I]_(o)) and [S]_(o) is the substrate concentration used. The resulting data are fitted using linear regression and the resulting slope, 1/(K_(i)(1+[S]_(o)/K_(m)), is used to calculate the K_(i) value. The Ki* values of some of the inventive compounds are shown in Table 6 and Table 6A below:

TABLE 6 Example Ki* # Structure (nM) 1654

12 1655

24 1631

15 1606

16 1025

6.7 1024

7.3 1086

8 1090

9 1085

11 1023

33 1012

40 1056

30 1029

14 1095

8 1098

15

TABLE 6A Example Ki* # Structure (nM) 1104

13 1108

9 1109

27 1112

20 1114

32 1115

7.4 1116

34 1117

19 1120

30 1121

22

While the present invention has been described with in conjunction with the specific embodiments set forth above, many alternatives, modifications and other variations thereof will be apparent to those of ordinary skill in the art. All such alternatives, modifications and variations are intended to fall within the spirit and scope of the present invention. 

1. A compound, or enantiomers, stereoisomers, rotamers, tautomers, or racemates of said compound, or a pharmaceutically acceptable salt, solvate or ester of said compound, said compound having the general structure shown in Formula I:

wherein: R¹ is H, OR⁸, NR⁹R¹⁰, or CHR⁹R¹⁰, wherein R⁸, R⁹ and R¹⁰ can be the same or different, each being independently selected from the group consisting of H, alkyl-, alkenyl-, alkynyl-, aryl-, heteroaryl-, cycloalkyl-, heterocyclyl-, arylalkyl-, and heteroarylalkyl; or R¹⁰ is R¹⁴, wherein R¹⁴ is H, alkyl, aryl, heteroaryl, cycloalkyl, alkyl-aryl, alkyl-heteroaryl, aryl-alkyl, alkenyl, alkynyl or heteroaryl-alkyl; A and M can be the same or different, each being independently selected from R, OR, NHR, NRR′, SR, SO₂R, and halo; or A and M are connected to each other such that the moiety:

shown above in Formula I forms either a three, four, six, seven or eight-membered cycloalkyl, a four to eight-membered heterocyclyl, a six to ten-membered aryl, or a five to ten-membered heteroaryl; E is C(H) or C(R); L is C(H), or C(R); R, R′, R², and R³ can be the same or different, each being independently selected from the group consisting of H, alkyl-, alkenyl-, alkynyl-, cycloalkyl-, heteroalkyl-, heterocyclyl-, aryl-, heteroaryl-, (cycloalkyl)alkyl-, (heterocyclyl)alkyl-, aryl-alkyl-, and heteroaryl-alkyl-; or alternately R and R′ in NRR′ are connected to each other such that NRR′ forms a four to eight-membered heterocyclyl; and Y is:

wherein G is NH; and R¹⁵, R¹⁶, R¹⁷, and R¹⁸ can be the same or different, each being independently selected from the group consisting of H, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, cycloalkyl, heterocyclyl, aryl, arylalkyl, heteroaryl, and heteroarylalkyl, or alternately, (i) R¹⁵ and R¹⁶ are connected to each other to form a four to eight-membered cyclic structure, and (ii) likewise, independently, R¹⁷ and R¹⁸ are connected to each other to form a three to eight-membered cycloalkyl or heterocyclyl; wherein each of said alkyl, aryl, heteroaryl, cycloalkyl or heterocyclyl can be unsubstituted or optionally independently substituted with one or more moieties selected from the group consisting of: hydroxy, alkoxy, aryloxy, thio, alkylthio, arylthio, amino, amido, alkylamino, arylamino, alkylsulfonyl, arylsulfonyl, sulfonamido, alkylsulfonamido, arylsulfonamido, alkyl, aryl, heteroaryl, keto, carboxy, carbalkoxy, carboxamido, alkoxycarbonylamino, alkoxycarbonyloxy, alkylureido, arylureido, halo, cyano, and nitro.
 2. The compound of claim 1, wherein R′ is NR⁹R¹⁰, and R⁹ is H, R¹⁰ is H, or R¹⁴ wherein R¹⁴ is H, alkyl, aryl, heteroaryl, cycloalkyl, alkyl-aryl, alkyl-heteroaryl, aryl-alkyl, alkenyl, alkynyl or heteroaryl-alkyl.
 3. The compound of claim 2, wherein R¹⁴ is selected from the group consisting of:


4. The compound of claim 1, wherein R² is selected from the group consisting of the following moieties:


5. The compound of claim 1, wherein R³ is selected from the group consisting of:

wherein R³¹ is OH or O-alkyl; and R³² is H, C(O)CH₃, C(O)OtBu or C(O)N(H)tBu.
 6. The compound of claim 5, wherein R³ is selected from the group consisting of the following moieties:


7. The compound of claim 1, wherein

is selected from the group consisting of:

wherein Y³² is selected from the group consisting of:

R¹⁶ is selected from H, methyl, phenyl, benzyl; and R¹⁵ is selected from the following:


8. The compound of claim 7, wherein R¹⁶ is H.
 9. The compound of claim 1, wherein the moiety:

is selected from the following structures:


10. The compound of claim 9, wherein the moiety:

is selected from the following structures:


11. The compound of claim 10, wherein the moiety:

is seleted from the following structures:


12. The compound of claim 1, wherein R¹⁴ is selected from the group consisting of:

R² is selected from the group consisting of the following moieties:

R³ is selected from the group consisting of the following moieties:

Y is selected from the group consisting of:

wherein G=NH; and the moiety:

is selected from the group consisting of:

R¹⁶=H; and R¹⁵ is selected from one of the following:

and the moiety:

is:


13. A pharmaceutical composition comprising as an active ingredient at least one compound of claim
 1. 14. The pharmaceutical composition of claim 13 for use in treating an infection of hepatitis C virus (“HCV”).
 15. The pharmaceutical composition of claim 14 additionally comprising at least one pharmaceutically acceptable carrier.
 16. The pharmaceutical composition of claim 15, additionally containing at least one antiviral agent.
 17. The pharmaceutical composition of claim 16, still additionally containing at least one interferon.
 18. The pharmaceutical composition of claim 17, wherein said at least one antiviral agent is ribavirin and said at least one interferon is α-interferon or pegylated interferon.
 19. A compound exhibiting HCV protease inhibitory activity, or enantiomers, stereoisomers, rotamers, tautomers, diastereomers, or racemates of said compound, or a pharmaceutically acceptable salt, solvate or ester of said compound, said compound being selected from the compounds of structures listed below:


20. A pharmaceutical composition for treating disorders associated with the HCV, said composition comprising therapeutically effective amount of one or more compounds in claim 19 and a pharmaceutically acceptable carrier.
 21. The pharmaceutical composition of claim 20, additionally containing at least one antiviral agent.
 22. The pharmaceutical composition of claim 21, additionally containing at least one interferon or PEG-interferon alpha conjugate.
 23. The pharmaceutical composition of claim 22, wherein said at least one antiviral agent is ribavirin and said at least one interferon is α-interferon or pegylated interferon.
 24. A compound of claim 1 in purified form. 